Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * postgres_fdw.c
4 : : * Foreign-data wrapper for remote PostgreSQL servers
5 : : *
6 : : * Portions Copyright (c) 2012-2025, PostgreSQL Global Development Group
7 : : *
8 : : * IDENTIFICATION
9 : : * contrib/postgres_fdw/postgres_fdw.c
10 : : *
11 : : *-------------------------------------------------------------------------
12 : : */
13 : : #include "postgres.h"
14 : :
15 : : #include <limits.h>
16 : :
17 : : #include "access/htup_details.h"
18 : : #include "access/sysattr.h"
19 : : #include "access/table.h"
20 : : #include "catalog/pg_opfamily.h"
21 : : #include "commands/defrem.h"
22 : : #include "commands/explain_format.h"
23 : : #include "commands/explain_state.h"
24 : : #include "executor/execAsync.h"
25 : : #include "foreign/fdwapi.h"
26 : : #include "funcapi.h"
27 : : #include "miscadmin.h"
28 : : #include "nodes/makefuncs.h"
29 : : #include "nodes/nodeFuncs.h"
30 : : #include "optimizer/appendinfo.h"
31 : : #include "optimizer/cost.h"
32 : : #include "optimizer/inherit.h"
33 : : #include "optimizer/optimizer.h"
34 : : #include "optimizer/pathnode.h"
35 : : #include "optimizer/paths.h"
36 : : #include "optimizer/planmain.h"
37 : : #include "optimizer/prep.h"
38 : : #include "optimizer/restrictinfo.h"
39 : : #include "optimizer/tlist.h"
40 : : #include "parser/parsetree.h"
41 : : #include "postgres_fdw.h"
42 : : #include "storage/latch.h"
43 : : #include "utils/builtins.h"
44 : : #include "utils/float.h"
45 : : #include "utils/guc.h"
46 : : #include "utils/lsyscache.h"
47 : : #include "utils/memutils.h"
48 : : #include "utils/rel.h"
49 : : #include "utils/sampling.h"
50 : : #include "utils/selfuncs.h"
51 : :
164 tgl@sss.pgh.pa.us 52 :CBC 26 : PG_MODULE_MAGIC_EXT(
53 : : .name = "postgres_fdw",
54 : : .version = PG_VERSION
55 : : );
56 : :
57 : : /* Default CPU cost to start up a foreign query. */
58 : : #define DEFAULT_FDW_STARTUP_COST 100.0
59 : :
60 : : /* Default CPU cost to process 1 row (above and beyond cpu_tuple_cost). */
61 : : #define DEFAULT_FDW_TUPLE_COST 0.2
62 : :
63 : : /* If no remote estimates, assume a sort costs 20% extra */
64 : : #define DEFAULT_FDW_SORT_MULTIPLIER 1.2
65 : :
66 : : /*
67 : : * Indexes of FDW-private information stored in fdw_private lists.
68 : : *
69 : : * These items are indexed with the enum FdwScanPrivateIndex, so an item
70 : : * can be fetched with list_nth(). For example, to get the SELECT statement:
71 : : * sql = strVal(list_nth(fdw_private, FdwScanPrivateSelectSql));
72 : : */
73 : : enum FdwScanPrivateIndex
74 : : {
75 : : /* SQL statement to execute remotely (as a String node) */
76 : : FdwScanPrivateSelectSql,
77 : : /* Integer list of attribute numbers retrieved by the SELECT */
78 : : FdwScanPrivateRetrievedAttrs,
79 : : /* Integer representing the desired fetch_size */
80 : : FdwScanPrivateFetchSize,
81 : :
82 : : /*
83 : : * String describing join i.e. names of relations being joined and types
84 : : * of join, added when the scan is join
85 : : */
86 : : FdwScanPrivateRelations,
87 : : };
88 : :
89 : : /*
90 : : * Similarly, this enum describes what's kept in the fdw_private list for
91 : : * a ModifyTable node referencing a postgres_fdw foreign table. We store:
92 : : *
93 : : * 1) INSERT/UPDATE/DELETE statement text to be sent to the remote server
94 : : * 2) Integer list of target attribute numbers for INSERT/UPDATE
95 : : * (NIL for a DELETE)
96 : : * 3) Length till the end of VALUES clause for INSERT
97 : : * (-1 for a DELETE/UPDATE)
98 : : * 4) Boolean flag showing if the remote query has a RETURNING clause
99 : : * 5) Integer list of attribute numbers retrieved by RETURNING, if any
100 : : */
101 : : enum FdwModifyPrivateIndex
102 : : {
103 : : /* SQL statement to execute remotely (as a String node) */
104 : : FdwModifyPrivateUpdateSql,
105 : : /* Integer list of target attribute numbers for INSERT/UPDATE */
106 : : FdwModifyPrivateTargetAttnums,
107 : : /* Length till the end of VALUES clause (as an Integer node) */
108 : : FdwModifyPrivateLen,
109 : : /* has-returning flag (as a Boolean node) */
110 : : FdwModifyPrivateHasReturning,
111 : : /* Integer list of attribute numbers retrieved by RETURNING */
112 : : FdwModifyPrivateRetrievedAttrs,
113 : : };
114 : :
115 : : /*
116 : : * Similarly, this enum describes what's kept in the fdw_private list for
117 : : * a ForeignScan node that modifies a foreign table directly. We store:
118 : : *
119 : : * 1) UPDATE/DELETE statement text to be sent to the remote server
120 : : * 2) Boolean flag showing if the remote query has a RETURNING clause
121 : : * 3) Integer list of attribute numbers retrieved by RETURNING, if any
122 : : * 4) Boolean flag showing if we set the command es_processed
123 : : */
124 : : enum FdwDirectModifyPrivateIndex
125 : : {
126 : : /* SQL statement to execute remotely (as a String node) */
127 : : FdwDirectModifyPrivateUpdateSql,
128 : : /* has-returning flag (as a Boolean node) */
129 : : FdwDirectModifyPrivateHasReturning,
130 : : /* Integer list of attribute numbers retrieved by RETURNING */
131 : : FdwDirectModifyPrivateRetrievedAttrs,
132 : : /* set-processed flag (as a Boolean node) */
133 : : FdwDirectModifyPrivateSetProcessed,
134 : : };
135 : :
136 : : /*
137 : : * Execution state of a foreign scan using postgres_fdw.
138 : : */
139 : : typedef struct PgFdwScanState
140 : : {
141 : : Relation rel; /* relcache entry for the foreign table. NULL
142 : : * for a foreign join scan. */
143 : : TupleDesc tupdesc; /* tuple descriptor of scan */
144 : : AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
145 : :
146 : : /* extracted fdw_private data */
147 : : char *query; /* text of SELECT command */
148 : : List *retrieved_attrs; /* list of retrieved attribute numbers */
149 : :
150 : : /* for remote query execution */
151 : : PGconn *conn; /* connection for the scan */
152 : : PgFdwConnState *conn_state; /* extra per-connection state */
153 : : unsigned int cursor_number; /* quasi-unique ID for my cursor */
154 : : bool cursor_exists; /* have we created the cursor? */
155 : : int numParams; /* number of parameters passed to query */
156 : : FmgrInfo *param_flinfo; /* output conversion functions for them */
157 : : List *param_exprs; /* executable expressions for param values */
158 : : const char **param_values; /* textual values of query parameters */
159 : :
160 : : /* for storing result tuples */
161 : : HeapTuple *tuples; /* array of currently-retrieved tuples */
162 : : int num_tuples; /* # of tuples in array */
163 : : int next_tuple; /* index of next one to return */
164 : :
165 : : /* batch-level state, for optimizing rewinds and avoiding useless fetch */
166 : : int fetch_ct_2; /* Min(# of fetches done, 2) */
167 : : bool eof_reached; /* true if last fetch reached EOF */
168 : :
169 : : /* for asynchronous execution */
170 : : bool async_capable; /* engage asynchronous-capable logic? */
171 : :
172 : : /* working memory contexts */
173 : : MemoryContext batch_cxt; /* context holding current batch of tuples */
174 : : MemoryContext temp_cxt; /* context for per-tuple temporary data */
175 : :
176 : : int fetch_size; /* number of tuples per fetch */
177 : : } PgFdwScanState;
178 : :
179 : : /*
180 : : * Execution state of a foreign insert/update/delete operation.
181 : : */
182 : : typedef struct PgFdwModifyState
183 : : {
184 : : Relation rel; /* relcache entry for the foreign table */
185 : : AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
186 : :
187 : : /* for remote query execution */
188 : : PGconn *conn; /* connection for the scan */
189 : : PgFdwConnState *conn_state; /* extra per-connection state */
190 : : char *p_name; /* name of prepared statement, if created */
191 : :
192 : : /* extracted fdw_private data */
193 : : char *query; /* text of INSERT/UPDATE/DELETE command */
194 : : char *orig_query; /* original text of INSERT command */
195 : : List *target_attrs; /* list of target attribute numbers */
196 : : int values_end; /* length up to the end of VALUES */
197 : : int batch_size; /* value of FDW option "batch_size" */
198 : : bool has_returning; /* is there a RETURNING clause? */
199 : : List *retrieved_attrs; /* attr numbers retrieved by RETURNING */
200 : :
201 : : /* info about parameters for prepared statement */
202 : : AttrNumber ctidAttno; /* attnum of input resjunk ctid column */
203 : : int p_nums; /* number of parameters to transmit */
204 : : FmgrInfo *p_flinfo; /* output conversion functions for them */
205 : :
206 : : /* batch operation stuff */
207 : : int num_slots; /* number of slots to insert */
208 : :
209 : : /* working memory context */
210 : : MemoryContext temp_cxt; /* context for per-tuple temporary data */
211 : :
212 : : /* for update row movement if subplan result rel */
213 : : struct PgFdwModifyState *aux_fmstate; /* foreign-insert state, if
214 : : * created */
215 : : } PgFdwModifyState;
216 : :
217 : : /*
218 : : * Execution state of a foreign scan that modifies a foreign table directly.
219 : : */
220 : : typedef struct PgFdwDirectModifyState
221 : : {
222 : : Relation rel; /* relcache entry for the foreign table */
223 : : AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
224 : :
225 : : /* extracted fdw_private data */
226 : : char *query; /* text of UPDATE/DELETE command */
227 : : bool has_returning; /* is there a RETURNING clause? */
228 : : List *retrieved_attrs; /* attr numbers retrieved by RETURNING */
229 : : bool set_processed; /* do we set the command es_processed? */
230 : :
231 : : /* for remote query execution */
232 : : PGconn *conn; /* connection for the update */
233 : : PgFdwConnState *conn_state; /* extra per-connection state */
234 : : int numParams; /* number of parameters passed to query */
235 : : FmgrInfo *param_flinfo; /* output conversion functions for them */
236 : : List *param_exprs; /* executable expressions for param values */
237 : : const char **param_values; /* textual values of query parameters */
238 : :
239 : : /* for storing result tuples */
240 : : PGresult *result; /* result for query */
241 : : int num_tuples; /* # of result tuples */
242 : : int next_tuple; /* index of next one to return */
243 : : Relation resultRel; /* relcache entry for the target relation */
244 : : AttrNumber *attnoMap; /* array of attnums of input user columns */
245 : : AttrNumber ctidAttno; /* attnum of input ctid column */
246 : : AttrNumber oidAttno; /* attnum of input oid column */
247 : : bool hasSystemCols; /* are there system columns of resultRel? */
248 : :
249 : : /* working memory context */
250 : : MemoryContext temp_cxt; /* context for per-tuple temporary data */
251 : : } PgFdwDirectModifyState;
252 : :
253 : : /*
254 : : * Workspace for analyzing a foreign table.
255 : : */
256 : : typedef struct PgFdwAnalyzeState
257 : : {
258 : : Relation rel; /* relcache entry for the foreign table */
259 : : AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
260 : : List *retrieved_attrs; /* attr numbers retrieved by query */
261 : :
262 : : /* collected sample rows */
263 : : HeapTuple *rows; /* array of size targrows */
264 : : int targrows; /* target # of sample rows */
265 : : int numrows; /* # of sample rows collected */
266 : :
267 : : /* for random sampling */
268 : : double samplerows; /* # of rows fetched */
269 : : double rowstoskip; /* # of rows to skip before next sample */
270 : : ReservoirStateData rstate; /* state for reservoir sampling */
271 : :
272 : : /* working memory contexts */
273 : : MemoryContext anl_cxt; /* context for per-analyze lifespan data */
274 : : MemoryContext temp_cxt; /* context for per-tuple temporary data */
275 : : } PgFdwAnalyzeState;
276 : :
277 : : /*
278 : : * This enum describes what's kept in the fdw_private list for a ForeignPath.
279 : : * We store:
280 : : *
281 : : * 1) Boolean flag showing if the remote query has the final sort
282 : : * 2) Boolean flag showing if the remote query has the LIMIT clause
283 : : */
284 : : enum FdwPathPrivateIndex
285 : : {
286 : : /* has-final-sort flag (as a Boolean node) */
287 : : FdwPathPrivateHasFinalSort,
288 : : /* has-limit flag (as a Boolean node) */
289 : : FdwPathPrivateHasLimit,
290 : : };
291 : :
292 : : /* Struct for extra information passed to estimate_path_cost_size() */
293 : : typedef struct
294 : : {
295 : : PathTarget *target;
296 : : bool has_final_sort;
297 : : bool has_limit;
298 : : double limit_tuples;
299 : : int64 count_est;
300 : : int64 offset_est;
301 : : } PgFdwPathExtraData;
302 : :
303 : : /*
304 : : * Identify the attribute where data conversion fails.
305 : : */
306 : : typedef struct ConversionLocation
307 : : {
308 : : AttrNumber cur_attno; /* attribute number being processed, or 0 */
309 : : Relation rel; /* foreign table being processed, or NULL */
310 : : ForeignScanState *fsstate; /* plan node being processed, or NULL */
311 : : } ConversionLocation;
312 : :
313 : : /* Callback argument for ec_member_matches_foreign */
314 : : typedef struct
315 : : {
316 : : Expr *current; /* current expr, or NULL if not yet found */
317 : : List *already_used; /* expressions already dealt with */
318 : : } ec_member_foreign_arg;
319 : :
320 : : /*
321 : : * SQL functions
322 : : */
4580 323 : 17 : PG_FUNCTION_INFO_V1(postgres_fdw_handler);
324 : :
325 : : /*
326 : : * FDW callback routines
327 : : */
328 : : static void postgresGetForeignRelSize(PlannerInfo *root,
329 : : RelOptInfo *baserel,
330 : : Oid foreigntableid);
331 : : static void postgresGetForeignPaths(PlannerInfo *root,
332 : : RelOptInfo *baserel,
333 : : Oid foreigntableid);
334 : : static ForeignScan *postgresGetForeignPlan(PlannerInfo *root,
335 : : RelOptInfo *foreignrel,
336 : : Oid foreigntableid,
337 : : ForeignPath *best_path,
338 : : List *tlist,
339 : : List *scan_clauses,
340 : : Plan *outer_plan);
341 : : static void postgresBeginForeignScan(ForeignScanState *node, int eflags);
342 : : static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node);
343 : : static void postgresReScanForeignScan(ForeignScanState *node);
344 : : static void postgresEndForeignScan(ForeignScanState *node);
345 : : static void postgresAddForeignUpdateTargets(PlannerInfo *root,
346 : : Index rtindex,
347 : : RangeTblEntry *target_rte,
348 : : Relation target_relation);
349 : : static List *postgresPlanForeignModify(PlannerInfo *root,
350 : : ModifyTable *plan,
351 : : Index resultRelation,
352 : : int subplan_index);
353 : : static void postgresBeginForeignModify(ModifyTableState *mtstate,
354 : : ResultRelInfo *resultRelInfo,
355 : : List *fdw_private,
356 : : int subplan_index,
357 : : int eflags);
358 : : static TupleTableSlot *postgresExecForeignInsert(EState *estate,
359 : : ResultRelInfo *resultRelInfo,
360 : : TupleTableSlot *slot,
361 : : TupleTableSlot *planSlot);
362 : : static TupleTableSlot **postgresExecForeignBatchInsert(EState *estate,
363 : : ResultRelInfo *resultRelInfo,
364 : : TupleTableSlot **slots,
365 : : TupleTableSlot **planSlots,
366 : : int *numSlots);
367 : : static int postgresGetForeignModifyBatchSize(ResultRelInfo *resultRelInfo);
368 : : static TupleTableSlot *postgresExecForeignUpdate(EState *estate,
369 : : ResultRelInfo *resultRelInfo,
370 : : TupleTableSlot *slot,
371 : : TupleTableSlot *planSlot);
372 : : static TupleTableSlot *postgresExecForeignDelete(EState *estate,
373 : : ResultRelInfo *resultRelInfo,
374 : : TupleTableSlot *slot,
375 : : TupleTableSlot *planSlot);
376 : : static void postgresEndForeignModify(EState *estate,
377 : : ResultRelInfo *resultRelInfo);
378 : : static void postgresBeginForeignInsert(ModifyTableState *mtstate,
379 : : ResultRelInfo *resultRelInfo);
380 : : static void postgresEndForeignInsert(EState *estate,
381 : : ResultRelInfo *resultRelInfo);
382 : : static int postgresIsForeignRelUpdatable(Relation rel);
383 : : static bool postgresPlanDirectModify(PlannerInfo *root,
384 : : ModifyTable *plan,
385 : : Index resultRelation,
386 : : int subplan_index);
387 : : static void postgresBeginDirectModify(ForeignScanState *node, int eflags);
388 : : static TupleTableSlot *postgresIterateDirectModify(ForeignScanState *node);
389 : : static void postgresEndDirectModify(ForeignScanState *node);
390 : : static void postgresExplainForeignScan(ForeignScanState *node,
391 : : ExplainState *es);
392 : : static void postgresExplainForeignModify(ModifyTableState *mtstate,
393 : : ResultRelInfo *rinfo,
394 : : List *fdw_private,
395 : : int subplan_index,
396 : : ExplainState *es);
397 : : static void postgresExplainDirectModify(ForeignScanState *node,
398 : : ExplainState *es);
399 : : static void postgresExecForeignTruncate(List *rels,
400 : : DropBehavior behavior,
401 : : bool restart_seqs);
402 : : static bool postgresAnalyzeForeignTable(Relation relation,
403 : : AcquireSampleRowsFunc *func,
404 : : BlockNumber *totalpages);
405 : : static List *postgresImportForeignSchema(ImportForeignSchemaStmt *stmt,
406 : : Oid serverOid);
407 : : static void postgresGetForeignJoinPaths(PlannerInfo *root,
408 : : RelOptInfo *joinrel,
409 : : RelOptInfo *outerrel,
410 : : RelOptInfo *innerrel,
411 : : JoinType jointype,
412 : : JoinPathExtraData *extra);
413 : : static bool postgresRecheckForeignScan(ForeignScanState *node,
414 : : TupleTableSlot *slot);
415 : : static void postgresGetForeignUpperPaths(PlannerInfo *root,
416 : : UpperRelationKind stage,
417 : : RelOptInfo *input_rel,
418 : : RelOptInfo *output_rel,
419 : : void *extra);
420 : : static bool postgresIsForeignPathAsyncCapable(ForeignPath *path);
421 : : static void postgresForeignAsyncRequest(AsyncRequest *areq);
422 : : static void postgresForeignAsyncConfigureWait(AsyncRequest *areq);
423 : : static void postgresForeignAsyncNotify(AsyncRequest *areq);
424 : :
425 : : /*
426 : : * Helper functions
427 : : */
428 : : static void estimate_path_cost_size(PlannerInfo *root,
429 : : RelOptInfo *foreignrel,
430 : : List *param_join_conds,
431 : : List *pathkeys,
432 : : PgFdwPathExtraData *fpextra,
433 : : double *p_rows, int *p_width,
434 : : int *p_disabled_nodes,
435 : : Cost *p_startup_cost, Cost *p_total_cost);
436 : : static void get_remote_estimate(const char *sql,
437 : : PGconn *conn,
438 : : double *rows,
439 : : int *width,
440 : : Cost *startup_cost,
441 : : Cost *total_cost);
442 : : static void adjust_foreign_grouping_path_cost(PlannerInfo *root,
443 : : List *pathkeys,
444 : : double retrieved_rows,
445 : : double width,
446 : : double limit_tuples,
447 : : int *p_disabled_nodes,
448 : : Cost *p_startup_cost,
449 : : Cost *p_run_cost);
450 : : static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
451 : : EquivalenceClass *ec, EquivalenceMember *em,
452 : : void *arg);
453 : : static void create_cursor(ForeignScanState *node);
454 : : static void fetch_more_data(ForeignScanState *node);
455 : : static void close_cursor(PGconn *conn, unsigned int cursor_number,
456 : : PgFdwConnState *conn_state);
457 : : static PgFdwModifyState *create_foreign_modify(EState *estate,
458 : : RangeTblEntry *rte,
459 : : ResultRelInfo *resultRelInfo,
460 : : CmdType operation,
461 : : Plan *subplan,
462 : : char *query,
463 : : List *target_attrs,
464 : : int values_end,
465 : : bool has_returning,
466 : : List *retrieved_attrs);
467 : : static TupleTableSlot **execute_foreign_modify(EState *estate,
468 : : ResultRelInfo *resultRelInfo,
469 : : CmdType operation,
470 : : TupleTableSlot **slots,
471 : : TupleTableSlot **planSlots,
472 : : int *numSlots);
473 : : static void prepare_foreign_modify(PgFdwModifyState *fmstate);
474 : : static const char **convert_prep_stmt_params(PgFdwModifyState *fmstate,
475 : : ItemPointer tupleid,
476 : : TupleTableSlot **slots,
477 : : int numSlots);
478 : : static void store_returning_result(PgFdwModifyState *fmstate,
479 : : TupleTableSlot *slot, PGresult *res);
480 : : static void finish_foreign_modify(PgFdwModifyState *fmstate);
481 : : static void deallocate_query(PgFdwModifyState *fmstate);
482 : : static List *build_remote_returning(Index rtindex, Relation rel,
483 : : List *returningList);
484 : : static void rebuild_fdw_scan_tlist(ForeignScan *fscan, List *tlist);
485 : : static void execute_dml_stmt(ForeignScanState *node);
486 : : static TupleTableSlot *get_returning_data(ForeignScanState *node);
487 : : static void init_returning_filter(PgFdwDirectModifyState *dmstate,
488 : : List *fdw_scan_tlist,
489 : : Index rtindex);
490 : : static TupleTableSlot *apply_returning_filter(PgFdwDirectModifyState *dmstate,
491 : : ResultRelInfo *resultRelInfo,
492 : : TupleTableSlot *slot,
493 : : EState *estate);
494 : : static void prepare_query_params(PlanState *node,
495 : : List *fdw_exprs,
496 : : int numParams,
497 : : FmgrInfo **param_flinfo,
498 : : List **param_exprs,
499 : : const char ***param_values);
500 : : static void process_query_params(ExprContext *econtext,
501 : : FmgrInfo *param_flinfo,
502 : : List *param_exprs,
503 : : const char **param_values);
504 : : static int postgresAcquireSampleRowsFunc(Relation relation, int elevel,
505 : : HeapTuple *rows, int targrows,
506 : : double *totalrows,
507 : : double *totaldeadrows);
508 : : static void analyze_row_processor(PGresult *res, int row,
509 : : PgFdwAnalyzeState *astate);
510 : : static void produce_tuple_asynchronously(AsyncRequest *areq, bool fetch);
511 : : static void fetch_more_data_begin(AsyncRequest *areq);
512 : : static void complete_pending_request(AsyncRequest *areq);
513 : : static HeapTuple make_tuple_from_result_row(PGresult *res,
514 : : int row,
515 : : Relation rel,
516 : : AttInMetadata *attinmeta,
517 : : List *retrieved_attrs,
518 : : ForeignScanState *fsstate,
519 : : MemoryContext temp_context);
520 : : static void conversion_error_callback(void *arg);
521 : : static bool foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel,
522 : : JoinType jointype, RelOptInfo *outerrel, RelOptInfo *innerrel,
523 : : JoinPathExtraData *extra);
524 : : static bool foreign_grouping_ok(PlannerInfo *root, RelOptInfo *grouped_rel,
525 : : Node *havingQual);
526 : : static List *get_useful_pathkeys_for_relation(PlannerInfo *root,
527 : : RelOptInfo *rel);
528 : : static List *get_useful_ecs_for_relation(PlannerInfo *root, RelOptInfo *rel);
529 : : static void add_paths_with_pathkeys_for_rel(PlannerInfo *root, RelOptInfo *rel,
530 : : Path *epq_path, List *restrictlist);
531 : : static void add_foreign_grouping_paths(PlannerInfo *root,
532 : : RelOptInfo *input_rel,
533 : : RelOptInfo *grouped_rel,
534 : : GroupPathExtraData *extra);
535 : : static void add_foreign_ordered_paths(PlannerInfo *root,
536 : : RelOptInfo *input_rel,
537 : : RelOptInfo *ordered_rel);
538 : : static void add_foreign_final_paths(PlannerInfo *root,
539 : : RelOptInfo *input_rel,
540 : : RelOptInfo *final_rel,
541 : : FinalPathExtraData *extra);
542 : : static void apply_server_options(PgFdwRelationInfo *fpinfo);
543 : : static void apply_table_options(PgFdwRelationInfo *fpinfo);
544 : : static void merge_fdw_options(PgFdwRelationInfo *fpinfo,
545 : : const PgFdwRelationInfo *fpinfo_o,
546 : : const PgFdwRelationInfo *fpinfo_i);
547 : : static int get_batch_size_option(Relation rel);
548 : :
549 : :
550 : : /*
551 : : * Foreign-data wrapper handler function: return a struct with pointers
552 : : * to my callback routines.
553 : : */
554 : : Datum
555 : 681 : postgres_fdw_handler(PG_FUNCTION_ARGS)
556 : : {
557 : 681 : FdwRoutine *routine = makeNode(FdwRoutine);
558 : :
559 : : /* Functions for scanning foreign tables */
560 : 681 : routine->GetForeignRelSize = postgresGetForeignRelSize;
561 : 681 : routine->GetForeignPaths = postgresGetForeignPaths;
562 : 681 : routine->GetForeignPlan = postgresGetForeignPlan;
563 : 681 : routine->BeginForeignScan = postgresBeginForeignScan;
564 : 681 : routine->IterateForeignScan = postgresIterateForeignScan;
565 : 681 : routine->ReScanForeignScan = postgresReScanForeignScan;
566 : 681 : routine->EndForeignScan = postgresEndForeignScan;
567 : :
568 : : /* Functions for updating foreign tables */
4563 569 : 681 : routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets;
570 : 681 : routine->PlanForeignModify = postgresPlanForeignModify;
571 : 681 : routine->BeginForeignModify = postgresBeginForeignModify;
572 : 681 : routine->ExecForeignInsert = postgresExecForeignInsert;
1690 tomas.vondra@postgre 573 : 681 : routine->ExecForeignBatchInsert = postgresExecForeignBatchInsert;
574 : 681 : routine->GetForeignModifyBatchSize = postgresGetForeignModifyBatchSize;
4563 tgl@sss.pgh.pa.us 575 : 681 : routine->ExecForeignUpdate = postgresExecForeignUpdate;
576 : 681 : routine->ExecForeignDelete = postgresExecForeignDelete;
577 : 681 : routine->EndForeignModify = postgresEndForeignModify;
2710 rhaas@postgresql.org 578 : 681 : routine->BeginForeignInsert = postgresBeginForeignInsert;
579 : 681 : routine->EndForeignInsert = postgresEndForeignInsert;
4469 tgl@sss.pgh.pa.us 580 : 681 : routine->IsForeignRelUpdatable = postgresIsForeignRelUpdatable;
3459 rhaas@postgresql.org 581 : 681 : routine->PlanDirectModify = postgresPlanDirectModify;
582 : 681 : routine->BeginDirectModify = postgresBeginDirectModify;
583 : 681 : routine->IterateDirectModify = postgresIterateDirectModify;
584 : 681 : routine->EndDirectModify = postgresEndDirectModify;
585 : :
586 : : /* Function for EvalPlanQual rechecks */
3497 587 : 681 : routine->RecheckForeignScan = postgresRecheckForeignScan;
588 : : /* Support functions for EXPLAIN */
4563 tgl@sss.pgh.pa.us 589 : 681 : routine->ExplainForeignScan = postgresExplainForeignScan;
590 : 681 : routine->ExplainForeignModify = postgresExplainForeignModify;
3459 rhaas@postgresql.org 591 : 681 : routine->ExplainDirectModify = postgresExplainDirectModify;
592 : :
593 : : /* Support function for TRUNCATE */
1612 fujii@postgresql.org 594 : 681 : routine->ExecForeignTruncate = postgresExecForeignTruncate;
595 : :
596 : : /* Support functions for ANALYZE */
4580 tgl@sss.pgh.pa.us 597 : 681 : routine->AnalyzeForeignTable = postgresAnalyzeForeignTable;
598 : :
599 : : /* Support functions for IMPORT FOREIGN SCHEMA */
4076 600 : 681 : routine->ImportForeignSchema = postgresImportForeignSchema;
601 : :
602 : : /* Support functions for join push-down */
3497 rhaas@postgresql.org 603 : 681 : routine->GetForeignJoinPaths = postgresGetForeignJoinPaths;
604 : :
605 : : /* Support functions for upper relation push-down */
3242 606 : 681 : routine->GetForeignUpperPaths = postgresGetForeignUpperPaths;
607 : :
608 : : /* Support functions for asynchronous execution */
1620 efujita@postgresql.o 609 : 681 : routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable;
610 : 681 : routine->ForeignAsyncRequest = postgresForeignAsyncRequest;
611 : 681 : routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait;
612 : 681 : routine->ForeignAsyncNotify = postgresForeignAsyncNotify;
613 : :
4580 tgl@sss.pgh.pa.us 614 : 681 : PG_RETURN_POINTER(routine);
615 : : }
616 : :
617 : : /*
618 : : * postgresGetForeignRelSize
619 : : * Estimate # of rows and width of the result of the scan
620 : : *
621 : : * We should consider the effect of all baserestrictinfo clauses here, but
622 : : * not any join clauses.
623 : : */
624 : : static void
625 : 1184 : postgresGetForeignRelSize(PlannerInfo *root,
626 : : RelOptInfo *baserel,
627 : : Oid foreigntableid)
628 : : {
629 : : PgFdwRelationInfo *fpinfo;
630 : : ListCell *lc;
631 : :
632 : : /*
633 : : * We use PgFdwRelationInfo to pass various information to subsequent
634 : : * functions.
635 : : */
4563 636 : 1184 : fpinfo = (PgFdwRelationInfo *) palloc0(sizeof(PgFdwRelationInfo));
282 peter@eisentraut.org 637 : 1184 : baserel->fdw_private = fpinfo;
638 : :
639 : : /* Base foreign tables need to be pushed down always. */
3497 rhaas@postgresql.org 640 : 1184 : fpinfo->pushdown_safe = true;
641 : :
642 : : /* Look up foreign-table catalog info. */
4552 tgl@sss.pgh.pa.us 643 : 1184 : fpinfo->table = GetForeignTable(foreigntableid);
644 : 1184 : fpinfo->server = GetForeignServer(fpinfo->table->serverid);
645 : :
646 : : /*
647 : : * Extract user-settable option values. Note that per-table settings of
648 : : * use_remote_estimate, fetch_size and async_capable override per-server
649 : : * settings of them, respectively.
650 : : */
651 : 1184 : fpinfo->use_remote_estimate = false;
652 : 1184 : fpinfo->fdw_startup_cost = DEFAULT_FDW_STARTUP_COST;
653 : 1184 : fpinfo->fdw_tuple_cost = DEFAULT_FDW_TUPLE_COST;
3595 654 : 1184 : fpinfo->shippable_extensions = NIL;
3503 rhaas@postgresql.org 655 : 1184 : fpinfo->fetch_size = 100;
1620 efujita@postgresql.o 656 : 1184 : fpinfo->async_capable = false;
657 : :
3057 peter_e@gmx.net 658 : 1184 : apply_server_options(fpinfo);
659 : 1184 : apply_table_options(fpinfo);
660 : :
661 : : /*
662 : : * If the table or the server is configured to use remote estimates,
663 : : * identify which user to do remote access as during planning. This
664 : : * should match what ExecCheckPermissions() does. If we fail due to lack
665 : : * of permissions, the query would have failed at runtime anyway.
666 : : */
4552 tgl@sss.pgh.pa.us 667 [ + + ]: 1184 : if (fpinfo->use_remote_estimate)
668 : : {
669 : : Oid userid;
670 : :
1011 alvherre@alvh.no-ip. 671 [ + + ]: 303 : userid = OidIsValid(baserel->userid) ? baserel->userid : GetUserId();
4552 tgl@sss.pgh.pa.us 672 : 303 : fpinfo->user = GetUserMapping(userid, fpinfo->server->serverid);
673 : : }
674 : : else
675 : 881 : fpinfo->user = NULL;
676 : :
677 : : /*
678 : : * Identify which baserestrictinfo clauses can be sent to the remote
679 : : * server and which can't.
680 : : */
4201 681 : 1182 : classifyConditions(root, baserel, baserel->baserestrictinfo,
682 : : &fpinfo->remote_conds, &fpinfo->local_conds);
683 : :
684 : : /*
685 : : * Identify which attributes will need to be retrieved from the remote
686 : : * server. These include all attrs needed for joins or final output, plus
687 : : * all attrs used in the local_conds. (Note: if we end up using a
688 : : * parameterized scan, it's possible that some of the join clauses will be
689 : : * sent to the remote and thus we wouldn't really need to retrieve the
690 : : * columns used in them. Doesn't seem worth detecting that case though.)
691 : : */
4552 692 : 1182 : fpinfo->attrs_used = NULL;
3463 693 : 1182 : pull_varattnos((Node *) baserel->reltarget->exprs, baserel->relid,
694 : : &fpinfo->attrs_used);
4552 695 [ + + + + : 1257 : foreach(lc, fpinfo->local_conds)
+ + ]
696 : : {
3070 697 : 75 : RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
698 : :
4563 699 : 75 : pull_varattnos((Node *) rinfo->clause, baserel->relid,
700 : : &fpinfo->attrs_used);
701 : : }
702 : :
703 : : /*
704 : : * Compute the selectivity and cost of the local_conds, so we don't have
705 : : * to do it over again for each path. The best we can do for these
706 : : * conditions is to estimate selectivity on the basis of local statistics.
707 : : */
4552 708 : 2364 : fpinfo->local_conds_sel = clauselist_selectivity(root,
709 : : fpinfo->local_conds,
710 : 1182 : baserel->relid,
711 : : JOIN_INNER,
712 : : NULL);
713 : :
714 : 1182 : cost_qual_eval(&fpinfo->local_conds_cost, fpinfo->local_conds, root);
715 : :
716 : : /*
717 : : * Set # of retrieved rows and cached relation costs to some negative
718 : : * value, so that we can detect when they are set to some sensible values,
719 : : * during one (usually the first) of the calls to estimate_path_cost_size.
720 : : */
2276 efujita@postgresql.o 721 : 1182 : fpinfo->retrieved_rows = -1;
3468 rhaas@postgresql.org 722 : 1182 : fpinfo->rel_startup_cost = -1;
723 : 1182 : fpinfo->rel_total_cost = -1;
724 : :
725 : : /*
726 : : * If the table or the server is configured to use remote estimates,
727 : : * connect to the foreign server and execute EXPLAIN to estimate the
728 : : * number of rows selected by the restriction clauses, as well as the
729 : : * average row width. Otherwise, estimate using whatever statistics we
730 : : * have locally, in a way similar to ordinary tables.
731 : : */
4552 tgl@sss.pgh.pa.us 732 [ + + ]: 1182 : if (fpinfo->use_remote_estimate)
733 : : {
734 : : /*
735 : : * Get cost/size estimates with help of remote server. Save the
736 : : * values in fpinfo so we don't need to do it again to generate the
737 : : * basic foreign path.
738 : : */
2349 efujita@postgresql.o 739 : 301 : estimate_path_cost_size(root, baserel, NIL, NIL, NULL,
740 : : &fpinfo->rows, &fpinfo->width,
741 : : &fpinfo->disabled_nodes,
742 : : &fpinfo->startup_cost, &fpinfo->total_cost);
743 : :
744 : : /* Report estimated baserel size to planner. */
4552 tgl@sss.pgh.pa.us 745 : 301 : baserel->rows = fpinfo->rows;
3463 746 : 301 : baserel->reltarget->width = fpinfo->width;
747 : : }
748 : : else
749 : : {
750 : : /*
751 : : * If the foreign table has never been ANALYZEd, it will have
752 : : * reltuples < 0, meaning "unknown". We can't do much if we're not
753 : : * allowed to consult the remote server, but we can use a hack similar
754 : : * to plancat.c's treatment of empty relations: use a minimum size
755 : : * estimate of 10 pages, and divide by the column-datatype-based width
756 : : * estimate to get the corresponding number of tuples.
757 : : */
1833 758 [ + + ]: 881 : if (baserel->tuples < 0)
759 : : {
4579 760 : 285 : baserel->pages = 10;
4580 761 : 285 : baserel->tuples =
3463 762 : 285 : (10 * BLCKSZ) / (baserel->reltarget->width +
763 : : MAXALIGN(SizeofHeapTupleHeader));
764 : : }
765 : :
766 : : /* Estimate baserel size as best we can with local statistics. */
4580 767 : 881 : set_baserel_size_estimates(root, baserel);
768 : :
769 : : /* Fill in basically-bogus cost estimates for use later. */
2349 efujita@postgresql.o 770 : 881 : estimate_path_cost_size(root, baserel, NIL, NIL, NULL,
771 : : &fpinfo->rows, &fpinfo->width,
772 : : &fpinfo->disabled_nodes,
773 : : &fpinfo->startup_cost, &fpinfo->total_cost);
774 : : }
775 : :
776 : : /*
777 : : * fpinfo->relation_name gets the numeric rangetable index of the foreign
778 : : * table RTE. (If this query gets EXPLAIN'd, we'll convert that to a
779 : : * human-readable string at that time.)
780 : : */
2105 tgl@sss.pgh.pa.us 781 : 1182 : fpinfo->relation_name = psprintf("%u", baserel->relid);
782 : :
783 : : /* No outer and inner relations. */
3096 rhaas@postgresql.org 784 : 1182 : fpinfo->make_outerrel_subquery = false;
785 : 1182 : fpinfo->make_innerrel_subquery = false;
786 : 1182 : fpinfo->lower_subquery_rels = NULL;
641 akorotkov@postgresql 787 : 1182 : fpinfo->hidden_subquery_rels = NULL;
788 : : /* Set the relation index. */
3096 rhaas@postgresql.org 789 : 1182 : fpinfo->relation_index = baserel->relid;
4580 tgl@sss.pgh.pa.us 790 : 1182 : }
791 : :
792 : : /*
793 : : * get_useful_ecs_for_relation
794 : : * Determine which EquivalenceClasses might be involved in useful
795 : : * orderings of this relation.
796 : : *
797 : : * This function is in some respects a mirror image of the core function
798 : : * pathkeys_useful_for_merging: for a regular table, we know what indexes
799 : : * we have and want to test whether any of them are useful. For a foreign
800 : : * table, we don't know what indexes are present on the remote side but
801 : : * want to speculate about which ones we'd like to use if they existed.
802 : : *
803 : : * This function returns a list of potentially-useful equivalence classes,
804 : : * but it does not guarantee that an EquivalenceMember exists which contains
805 : : * Vars only from the given relation. For example, given ft1 JOIN t1 ON
806 : : * ft1.x + t1.x = 0, this function will say that the equivalence class
807 : : * containing ft1.x + t1.x is potentially useful. Supposing ft1 is remote and
808 : : * t1 is local (or on a different server), it will turn out that no useful
809 : : * ORDER BY clause can be generated. It's not our job to figure that out
810 : : * here; we're only interested in identifying relevant ECs.
811 : : */
812 : : static List *
3546 rhaas@postgresql.org 813 : 522 : get_useful_ecs_for_relation(PlannerInfo *root, RelOptInfo *rel)
814 : : {
815 : 522 : List *useful_eclass_list = NIL;
816 : : ListCell *lc;
817 : : Relids relids;
818 : :
819 : : /*
820 : : * First, consider whether any active EC is potentially useful for a merge
821 : : * join against this relation.
822 : : */
823 [ + + ]: 522 : if (rel->has_eclass_joins)
824 : : {
825 [ + - + + : 670 : foreach(lc, root->eq_classes)
+ + ]
826 : : {
827 : 463 : EquivalenceClass *cur_ec = (EquivalenceClass *) lfirst(lc);
828 : :
829 [ + + ]: 463 : if (eclass_useful_for_merging(root, cur_ec, rel))
830 : 247 : useful_eclass_list = lappend(useful_eclass_list, cur_ec);
831 : : }
832 : : }
833 : :
834 : : /*
835 : : * Next, consider whether there are any non-EC derivable join clauses that
836 : : * are merge-joinable. If the joininfo list is empty, we can exit
837 : : * quickly.
838 : : */
839 [ + + ]: 522 : if (rel->joininfo == NIL)
840 : 380 : return useful_eclass_list;
841 : :
842 : : /* If this is a child rel, we must use the topmost parent rel to search. */
3078 843 [ + + + - : 142 : if (IS_OTHER_REL(rel))
- + ]
844 : : {
845 [ - + ]: 20 : Assert(!bms_is_empty(rel->top_parent_relids));
846 : 20 : relids = rel->top_parent_relids;
847 : : }
848 : : else
3546 849 : 122 : relids = rel->relids;
850 : :
851 : : /* Check each join clause in turn. */
852 [ + - + + : 345 : foreach(lc, rel->joininfo)
+ + ]
853 : : {
854 : 203 : RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(lc);
855 : :
856 : : /* Consider only mergejoinable clauses */
857 [ + + ]: 203 : if (restrictinfo->mergeopfamilies == NIL)
858 : 14 : continue;
859 : :
860 : : /* Make sure we've got canonical ECs. */
861 : 189 : update_mergeclause_eclasses(root, restrictinfo);
862 : :
863 : : /*
864 : : * restrictinfo->mergeopfamilies != NIL is sufficient to guarantee
865 : : * that left_ec and right_ec will be initialized, per comments in
866 : : * distribute_qual_to_rels.
867 : : *
868 : : * We want to identify which side of this merge-joinable clause
869 : : * contains columns from the relation produced by this RelOptInfo. We
870 : : * test for overlap, not containment, because there could be extra
871 : : * relations on either side. For example, suppose we've got something
872 : : * like ((A JOIN B ON A.x = B.x) JOIN C ON A.y = C.y) LEFT JOIN D ON
873 : : * A.y = D.y. The input rel might be the joinrel between A and B, and
874 : : * we'll consider the join clause A.y = D.y. relids contains a
875 : : * relation not involved in the join class (B) and the equivalence
876 : : * class for the left-hand side of the clause contains a relation not
877 : : * involved in the input rel (C). Despite the fact that we have only
878 : : * overlap and not containment in either direction, A.y is potentially
879 : : * useful as a sort column.
880 : : *
881 : : * Note that it's even possible that relids overlaps neither side of
882 : : * the join clause. For example, consider A LEFT JOIN B ON A.x = B.x
883 : : * AND A.x = 1. The clause A.x = 1 will appear in B's joininfo list,
884 : : * but overlaps neither side of B. In that case, we just skip this
885 : : * join clause, since it doesn't suggest a useful sort order for this
886 : : * relation.
887 : : */
3400 888 [ + + ]: 189 : if (bms_overlap(relids, restrictinfo->right_ec->ec_relids))
3546 889 : 86 : useful_eclass_list = list_append_unique_ptr(useful_eclass_list,
2999 tgl@sss.pgh.pa.us 890 : 86 : restrictinfo->right_ec);
3400 rhaas@postgresql.org 891 [ + + ]: 103 : else if (bms_overlap(relids, restrictinfo->left_ec->ec_relids))
3546 892 : 94 : useful_eclass_list = list_append_unique_ptr(useful_eclass_list,
2999 tgl@sss.pgh.pa.us 893 : 94 : restrictinfo->left_ec);
894 : : }
895 : :
3546 rhaas@postgresql.org 896 : 142 : return useful_eclass_list;
897 : : }
898 : :
899 : : /*
900 : : * get_useful_pathkeys_for_relation
901 : : * Determine which orderings of a relation might be useful.
902 : : *
903 : : * Getting data in sorted order can be useful either because the requested
904 : : * order matches the final output ordering for the overall query we're
905 : : * planning, or because it enables an efficient merge join. Here, we try
906 : : * to figure out which pathkeys to consider.
907 : : */
908 : : static List *
909 : 1515 : get_useful_pathkeys_for_relation(PlannerInfo *root, RelOptInfo *rel)
910 : : {
911 : 1515 : List *useful_pathkeys_list = NIL;
912 : : List *useful_eclass_list;
913 : 1515 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) rel->fdw_private;
914 : 1515 : EquivalenceClass *query_ec = NULL;
915 : : ListCell *lc;
916 : :
917 : : /*
918 : : * Pushing the query_pathkeys to the remote server is always worth
919 : : * considering, because it might let us avoid a local sort.
920 : : */
2349 efujita@postgresql.o 921 : 1515 : fpinfo->qp_is_pushdown_safe = false;
3546 rhaas@postgresql.org 922 [ + + ]: 1515 : if (root->query_pathkeys)
923 : : {
924 : 606 : bool query_pathkeys_ok = true;
925 : :
926 [ + - + + : 1144 : foreach(lc, root->query_pathkeys)
+ + ]
927 : : {
928 : 775 : PathKey *pathkey = (PathKey *) lfirst(lc);
929 : :
930 : : /*
931 : : * The planner and executor don't have any clever strategy for
932 : : * taking data sorted by a prefix of the query's pathkeys and
933 : : * getting it to be sorted by all of those pathkeys. We'll just
934 : : * end up resorting the entire data set. So, unless we can push
935 : : * down all of the query pathkeys, forget it.
936 : : */
1255 tgl@sss.pgh.pa.us 937 [ + + ]: 775 : if (!is_foreign_pathkey(root, rel, pathkey))
938 : : {
3546 rhaas@postgresql.org 939 : 237 : query_pathkeys_ok = false;
940 : 237 : break;
941 : : }
942 : : }
943 : :
944 [ + + ]: 606 : if (query_pathkeys_ok)
945 : : {
946 : 369 : useful_pathkeys_list = list_make1(list_copy(root->query_pathkeys));
2349 efujita@postgresql.o 947 : 369 : fpinfo->qp_is_pushdown_safe = true;
948 : : }
949 : : }
950 : :
951 : : /*
952 : : * Even if we're not using remote estimates, having the remote side do the
953 : : * sort generally won't be any worse than doing it locally, and it might
954 : : * be much better if the remote side can generate data in the right order
955 : : * without needing a sort at all. However, what we're going to do next is
956 : : * try to generate pathkeys that seem promising for possible merge joins,
957 : : * and that's more speculative. A wrong choice might hurt quite a bit, so
958 : : * bail out if we can't use remote estimates.
959 : : */
3546 rhaas@postgresql.org 960 [ + + ]: 1515 : if (!fpinfo->use_remote_estimate)
961 : 993 : return useful_pathkeys_list;
962 : :
963 : : /* Get the list of interesting EquivalenceClasses. */
964 : 522 : useful_eclass_list = get_useful_ecs_for_relation(root, rel);
965 : :
966 : : /* Extract unique EC for query, if any, so we don't consider it again. */
967 [ + + ]: 522 : if (list_length(root->query_pathkeys) == 1)
968 : : {
969 : 177 : PathKey *query_pathkey = linitial(root->query_pathkeys);
970 : :
971 : 177 : query_ec = query_pathkey->pk_eclass;
972 : : }
973 : :
974 : : /*
975 : : * As a heuristic, the only pathkeys we consider here are those of length
976 : : * one. It's surely possible to consider more, but since each one we
977 : : * choose to consider will generate a round-trip to the remote side, we
978 : : * need to be a bit cautious here. It would sure be nice to have a local
979 : : * cache of information about remote index definitions...
980 : : */
981 [ + + + + : 922 : foreach(lc, useful_eclass_list)
+ + ]
982 : : {
983 : 400 : EquivalenceClass *cur_ec = lfirst(lc);
984 : : PathKey *pathkey;
985 : :
986 : : /* If redundant with what we did above, skip it. */
987 [ + + ]: 400 : if (cur_ec == query_ec)
988 : 81 : continue;
989 : :
990 : : /* Can't push down the sort if the EC's opfamily is not shippable. */
1255 tgl@sss.pgh.pa.us 991 [ - + ]: 369 : if (!is_shippable(linitial_oid(cur_ec->ec_opfamilies),
992 : : OperatorFamilyRelationId, fpinfo))
1255 tgl@sss.pgh.pa.us 993 :UBC 0 : continue;
994 : :
995 : : /* If no pushable expression for this rel, skip it. */
1255 tgl@sss.pgh.pa.us 996 [ + + ]:CBC 369 : if (find_em_for_rel(root, cur_ec, rel) == NULL)
3546 rhaas@postgresql.org 997 : 50 : continue;
998 : :
999 : : /* Looks like we can generate a pathkey, so let's do it. */
1000 : 319 : pathkey = make_canonical_pathkey(root, cur_ec,
1001 : 319 : linitial_oid(cur_ec->ec_opfamilies),
1002 : : COMPARE_LT,
1003 : : false);
1004 : 319 : useful_pathkeys_list = lappend(useful_pathkeys_list,
1005 : 319 : list_make1(pathkey));
1006 : : }
1007 : :
1008 : 522 : return useful_pathkeys_list;
1009 : : }
1010 : :
1011 : : /*
1012 : : * postgresGetForeignPaths
1013 : : * Create possible scan paths for a scan on the foreign table
1014 : : */
1015 : : static void
4580 tgl@sss.pgh.pa.us 1016 : 1182 : postgresGetForeignPaths(PlannerInfo *root,
1017 : : RelOptInfo *baserel,
1018 : : Oid foreigntableid)
1019 : : {
1020 : 1182 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) baserel->fdw_private;
1021 : : ForeignPath *path;
1022 : : List *ppi_list;
1023 : : ListCell *lc;
1024 : :
1025 : : /*
1026 : : * Create simplest ForeignScan path node and add it to baserel. This path
1027 : : * corresponds to SeqScan path of regular tables (though depending on what
1028 : : * baserestrict conditions we were able to send to remote, there might
1029 : : * actually be an indexscan happening there). We already did all the work
1030 : : * to estimate cost and size of this path.
1031 : : *
1032 : : * Although this path uses no join clauses, it could still have required
1033 : : * parameterization due to LATERAL refs in its tlist.
1034 : : */
4552 1035 : 1182 : path = create_foreignscan_path(root, baserel,
1036 : : NULL, /* default pathtarget */
1037 : : fpinfo->rows,
1038 : : fpinfo->disabled_nodes,
1039 : : fpinfo->startup_cost,
1040 : : fpinfo->total_cost,
1041 : : NIL, /* no pathkeys */
1042 : : baserel->lateral_relids,
1043 : : NULL, /* no extra plan */
1044 : : NIL, /* no fdw_restrictinfo list */
1045 : : NIL); /* no fdw_private list */
1046 : 1182 : add_path(baserel, (Path *) path);
1047 : :
1048 : : /* Add paths with pathkeys */
753 efujita@postgresql.o 1049 : 1182 : add_paths_with_pathkeys_for_rel(root, baserel, NULL, NIL);
1050 : :
1051 : : /*
1052 : : * If we're not using remote estimates, stop here. We have no way to
1053 : : * estimate whether any join clauses would be worth sending across, so
1054 : : * don't bother building parameterized paths.
1055 : : */
4552 tgl@sss.pgh.pa.us 1056 [ + + ]: 1182 : if (!fpinfo->use_remote_estimate)
1057 : 881 : return;
1058 : :
1059 : : /*
1060 : : * Thumb through all join clauses for the rel to identify which outer
1061 : : * relations could supply one or more safe-to-send-to-remote join clauses.
1062 : : * We'll build a parameterized path for each such outer relation.
1063 : : *
1064 : : * It's convenient to manage this by representing each candidate outer
1065 : : * relation by the ParamPathInfo node for it. We can then use the
1066 : : * ppi_clauses list in the ParamPathInfo node directly as a list of the
1067 : : * interesting join clauses for that rel. This takes care of the
1068 : : * possibility that there are multiple safe join clauses for such a rel,
1069 : : * and also ensures that we account for unsafe join clauses that we'll
1070 : : * still have to enforce locally (since the parameterized-path machinery
1071 : : * insists that we handle all movable clauses).
1072 : : */
4201 1073 : 301 : ppi_list = NIL;
4552 1074 [ + + + + : 442 : foreach(lc, baserel->joininfo)
+ + ]
1075 : : {
1076 : 141 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
1077 : : Relids required_outer;
1078 : : ParamPathInfo *param_info;
1079 : :
1080 : : /* Check if clause can be moved to this rel */
4403 1081 [ + + ]: 141 : if (!join_clause_is_movable_to(rinfo, baserel))
4552 1082 : 96 : continue;
1083 : :
1084 : : /* See if it is safe to send to remote */
1085 [ + + ]: 45 : if (!is_foreign_expr(root, baserel, rinfo->clause))
1086 : 7 : continue;
1087 : :
1088 : : /* Calculate required outer rels for the resulting path */
1089 : 38 : required_outer = bms_union(rinfo->clause_relids,
1090 : 38 : baserel->lateral_relids);
1091 : : /* We do not want the foreign rel itself listed in required_outer */
1092 : 38 : required_outer = bms_del_member(required_outer, baserel->relid);
1093 : :
1094 : : /*
1095 : : * required_outer probably can't be empty here, but if it were, we
1096 : : * couldn't make a parameterized path.
1097 : : */
1098 [ - + ]: 38 : if (bms_is_empty(required_outer))
4201 tgl@sss.pgh.pa.us 1099 :UBC 0 : continue;
1100 : :
1101 : : /* Get the ParamPathInfo */
4201 tgl@sss.pgh.pa.us 1102 :CBC 38 : param_info = get_baserel_parampathinfo(root, baserel,
1103 : : required_outer);
1104 [ - + ]: 38 : Assert(param_info != NULL);
1105 : :
1106 : : /*
1107 : : * Add it to list unless we already have it. Testing pointer equality
1108 : : * is OK since get_baserel_parampathinfo won't make duplicates.
1109 : : */
1110 : 38 : ppi_list = list_append_unique_ptr(ppi_list, param_info);
1111 : : }
1112 : :
1113 : : /*
1114 : : * The above scan examined only "generic" join clauses, not those that
1115 : : * were absorbed into EquivalenceClauses. See if we can make anything out
1116 : : * of EquivalenceClauses.
1117 : : */
4552 1118 [ + + ]: 301 : if (baserel->has_eclass_joins)
1119 : : {
1120 : : /*
1121 : : * We repeatedly scan the eclass list looking for column references
1122 : : * (or expressions) belonging to the foreign rel. Each time we find
1123 : : * one, we generate a list of equivalence joinclauses for it, and then
1124 : : * see if any are safe to send to the remote. Repeat till there are
1125 : : * no more candidate EC members.
1126 : : */
1127 : : ec_member_foreign_arg arg;
1128 : :
1129 : 133 : arg.already_used = NIL;
1130 : : for (;;)
1131 : 141 : {
1132 : : List *clauses;
1133 : :
1134 : : /* Make clauses, skipping any that join to lateral_referencers */
1135 : 274 : arg.current = NULL;
1136 : 274 : clauses = generate_implied_equalities_for_column(root,
1137 : : baserel,
1138 : : ec_member_matches_foreign,
1139 : : &arg,
1140 : : baserel->lateral_referencers);
1141 : :
1142 : : /* Done if there are no more expressions in the foreign rel */
1143 [ + + ]: 274 : if (arg.current == NULL)
1144 : : {
1145 [ - + ]: 133 : Assert(clauses == NIL);
1146 : 133 : break;
1147 : : }
1148 : :
1149 : : /* Scan the extracted join clauses */
1150 [ + - + + : 314 : foreach(lc, clauses)
+ + ]
1151 : : {
1152 : 173 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
1153 : : Relids required_outer;
1154 : : ParamPathInfo *param_info;
1155 : :
1156 : : /* Check if clause can be moved to this rel */
4403 1157 [ - + ]: 173 : if (!join_clause_is_movable_to(rinfo, baserel))
4552 tgl@sss.pgh.pa.us 1158 :UBC 0 : continue;
1159 : :
1160 : : /* See if it is safe to send to remote */
4552 tgl@sss.pgh.pa.us 1161 [ + + ]:CBC 173 : if (!is_foreign_expr(root, baserel, rinfo->clause))
1162 : 7 : continue;
1163 : :
1164 : : /* Calculate required outer rels for the resulting path */
1165 : 166 : required_outer = bms_union(rinfo->clause_relids,
1166 : 166 : baserel->lateral_relids);
1167 : 166 : required_outer = bms_del_member(required_outer, baserel->relid);
1168 [ - + ]: 166 : if (bms_is_empty(required_outer))
4201 tgl@sss.pgh.pa.us 1169 :UBC 0 : continue;
1170 : :
1171 : : /* Get the ParamPathInfo */
4201 tgl@sss.pgh.pa.us 1172 :CBC 166 : param_info = get_baserel_parampathinfo(root, baserel,
1173 : : required_outer);
1174 [ - + ]: 166 : Assert(param_info != NULL);
1175 : :
1176 : : /* Add it to list unless we already have it */
1177 : 166 : ppi_list = list_append_unique_ptr(ppi_list, param_info);
1178 : : }
1179 : :
1180 : : /* Try again, now ignoring the expression we found this time */
4552 1181 : 141 : arg.already_used = lappend(arg.already_used, arg.current);
1182 : : }
1183 : : }
1184 : :
1185 : : /*
1186 : : * Now build a path for each useful outer relation.
1187 : : */
4201 1188 [ + + + + : 495 : foreach(lc, ppi_list)
+ + ]
1189 : : {
1190 : 194 : ParamPathInfo *param_info = (ParamPathInfo *) lfirst(lc);
1191 : : double rows;
1192 : : int width;
1193 : : int disabled_nodes;
1194 : : Cost startup_cost;
1195 : : Cost total_cost;
1196 : :
1197 : : /* Get a cost estimate from the remote */
1198 : 194 : estimate_path_cost_size(root, baserel,
1199 : : param_info->ppi_clauses, NIL, NULL,
1200 : : &rows, &width, &disabled_nodes,
1201 : : &startup_cost, &total_cost);
1202 : :
1203 : : /*
1204 : : * ppi_rows currently won't get looked at by anything, but still we
1205 : : * may as well ensure that it matches our idea of the rowcount.
1206 : : */
1207 : 194 : param_info->ppi_rows = rows;
1208 : :
1209 : : /* Make the path */
1210 : 194 : path = create_foreignscan_path(root, baserel,
1211 : : NULL, /* default pathtarget */
1212 : : rows,
1213 : : disabled_nodes,
1214 : : startup_cost,
1215 : : total_cost,
1216 : : NIL, /* no pathkeys */
1217 : : param_info->ppi_req_outer,
1218 : : NULL,
1219 : : NIL, /* no fdw_restrictinfo list */
1220 : : NIL); /* no fdw_private list */
1221 : 194 : add_path(baserel, (Path *) path);
1222 : : }
1223 : : }
1224 : :
1225 : : /*
1226 : : * postgresGetForeignPlan
1227 : : * Create ForeignScan plan node which implements selected best path
1228 : : */
1229 : : static ForeignScan *
4580 1230 : 996 : postgresGetForeignPlan(PlannerInfo *root,
1231 : : RelOptInfo *foreignrel,
1232 : : Oid foreigntableid,
1233 : : ForeignPath *best_path,
1234 : : List *tlist,
1235 : : List *scan_clauses,
1236 : : Plan *outer_plan)
1237 : : {
3497 rhaas@postgresql.org 1238 : 996 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) foreignrel->fdw_private;
1239 : : Index scan_relid;
1240 : : List *fdw_private;
3614 1241 : 996 : List *remote_exprs = NIL;
4580 tgl@sss.pgh.pa.us 1242 : 996 : List *local_exprs = NIL;
4552 1243 : 996 : List *params_list = NIL;
3070 1244 : 996 : List *fdw_scan_tlist = NIL;
1245 : 996 : List *fdw_recheck_quals = NIL;
1246 : : List *retrieved_attrs;
1247 : : StringInfoData sql;
2349 efujita@postgresql.o 1248 : 996 : bool has_final_sort = false;
1249 : 996 : bool has_limit = false;
1250 : : ListCell *lc;
1251 : :
1252 : : /*
1253 : : * Get FDW private data created by postgresGetForeignUpperPaths(), if any.
1254 : : */
1255 [ + + ]: 996 : if (best_path->fdw_private)
1256 : : {
1331 peter@eisentraut.org 1257 : 151 : has_final_sort = boolVal(list_nth(best_path->fdw_private,
1258 : : FdwPathPrivateHasFinalSort));
1259 : 151 : has_limit = boolVal(list_nth(best_path->fdw_private,
1260 : : FdwPathPrivateHasLimit));
1261 : : }
1262 : :
3078 rhaas@postgresql.org 1263 [ + + + + ]: 996 : if (IS_SIMPLE_REL(foreignrel))
1264 : : {
1265 : : /*
1266 : : * For base relations, set scan_relid as the relid of the relation.
1267 : : */
3497 1268 : 715 : scan_relid = foreignrel->relid;
1269 : :
1270 : : /*
1271 : : * In a base-relation scan, we must apply the given scan_clauses.
1272 : : *
1273 : : * Separate the scan_clauses into those that can be executed remotely
1274 : : * and those that can't. baserestrictinfo clauses that were
1275 : : * previously determined to be safe or unsafe by classifyConditions
1276 : : * are found in fpinfo->remote_conds and fpinfo->local_conds. Anything
1277 : : * else in the scan_clauses list will be a join clause, which we have
1278 : : * to check for remote-safety.
1279 : : *
1280 : : * Note: the join clauses we see here should be the exact same ones
1281 : : * previously examined by postgresGetForeignPaths. Possibly it'd be
1282 : : * worth passing forward the classification work done then, rather
1283 : : * than repeating it here.
1284 : : *
1285 : : * This code must match "extract_actual_clauses(scan_clauses, false)"
1286 : : * except for the additional decision about remote versus local
1287 : : * execution.
1288 : : */
3070 tgl@sss.pgh.pa.us 1289 [ + + + + : 1072 : foreach(lc, scan_clauses)
+ + ]
1290 : : {
1291 : 357 : RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
1292 : :
1293 : : /* Ignore any pseudoconstants, they're dealt with elsewhere */
1294 [ + + ]: 357 : if (rinfo->pseudoconstant)
1295 : 4 : continue;
1296 : :
1297 [ + + ]: 353 : if (list_member_ptr(fpinfo->remote_conds, rinfo))
1298 : 269 : remote_exprs = lappend(remote_exprs, rinfo->clause);
1299 [ + + ]: 84 : else if (list_member_ptr(fpinfo->local_conds, rinfo))
1300 : 71 : local_exprs = lappend(local_exprs, rinfo->clause);
1301 [ + + ]: 13 : else if (is_foreign_expr(root, foreignrel, rinfo->clause))
1302 : 11 : remote_exprs = lappend(remote_exprs, rinfo->clause);
1303 : : else
1304 : 2 : local_exprs = lappend(local_exprs, rinfo->clause);
1305 : : }
1306 : :
1307 : : /*
1308 : : * For a base-relation scan, we have to support EPQ recheck, which
1309 : : * should recheck all the remote quals.
1310 : : */
1311 : 715 : fdw_recheck_quals = remote_exprs;
1312 : : }
1313 : : else
1314 : : {
1315 : : /*
1316 : : * Join relation or upper relation - set scan_relid to 0.
1317 : : */
3497 rhaas@postgresql.org 1318 : 281 : scan_relid = 0;
1319 : :
1320 : : /*
1321 : : * For a join rel, baserestrictinfo is NIL and we are not considering
1322 : : * parameterization right now, so there should be no scan_clauses for
1323 : : * a joinrel or an upper rel either.
1324 : : */
1325 [ - + ]: 281 : Assert(!scan_clauses);
1326 : :
1327 : : /*
1328 : : * Instead we get the conditions to apply from the fdw_private
1329 : : * structure.
1330 : : */
3070 tgl@sss.pgh.pa.us 1331 : 281 : remote_exprs = extract_actual_clauses(fpinfo->remote_conds, false);
1332 : 281 : local_exprs = extract_actual_clauses(fpinfo->local_conds, false);
1333 : :
1334 : : /*
1335 : : * We leave fdw_recheck_quals empty in this case, since we never need
1336 : : * to apply EPQ recheck clauses. In the case of a joinrel, EPQ
1337 : : * recheck is handled elsewhere --- see postgresGetForeignJoinPaths().
1338 : : * If we're planning an upperrel (ie, remote grouping or aggregation)
1339 : : * then there's no EPQ to do because SELECT FOR UPDATE wouldn't be
1340 : : * allowed, and indeed we *can't* put the remote clauses into
1341 : : * fdw_recheck_quals because the unaggregated Vars won't be available
1342 : : * locally.
1343 : : */
1344 : :
1345 : : /* Build the list of columns to be fetched from the foreign server. */
3497 rhaas@postgresql.org 1346 : 281 : fdw_scan_tlist = build_tlist_to_deparse(foreignrel);
1347 : :
1348 : : /*
1349 : : * Ensure that the outer plan produces a tuple whose descriptor
1350 : : * matches our scan tuple slot. Also, remove the local conditions
1351 : : * from outer plan's quals, lest they be evaluated twice, once by the
1352 : : * local plan and once by the scan.
1353 : : */
1354 [ + + ]: 281 : if (outer_plan)
1355 : : {
1356 : : /*
1357 : : * Right now, we only consider grouping and aggregation beyond
1358 : : * joins. Queries involving aggregates or grouping do not require
1359 : : * EPQ mechanism, hence should not have an outer plan here.
1360 : : */
3078 1361 [ + - - + ]: 24 : Assert(!IS_UPPER_REL(foreignrel));
1362 : :
1363 : : /*
1364 : : * First, update the plan's qual list if possible. In some cases
1365 : : * the quals might be enforced below the topmost plan level, in
1366 : : * which case we'll fail to remove them; it's not worth working
1367 : : * harder than this.
1368 : : */
3497 1369 [ + + + + : 27 : foreach(lc, local_exprs)
+ + ]
1370 : : {
1371 : 3 : Node *qual = lfirst(lc);
1372 : :
1373 : 3 : outer_plan->qual = list_delete(outer_plan->qual, qual);
1374 : :
1375 : : /*
1376 : : * For an inner join the local conditions of foreign scan plan
1377 : : * can be part of the joinquals as well. (They might also be
1378 : : * in the mergequals or hashquals, but we can't touch those
1379 : : * without breaking the plan.)
1380 : : */
2460 tgl@sss.pgh.pa.us 1381 [ + + ]: 3 : if (IsA(outer_plan, NestLoop) ||
1382 [ + - ]: 1 : IsA(outer_plan, MergeJoin) ||
1383 [ - + ]: 1 : IsA(outer_plan, HashJoin))
1384 : : {
1385 : 2 : Join *join_plan = (Join *) outer_plan;
1386 : :
1387 [ + - ]: 2 : if (join_plan->jointype == JOIN_INNER)
1388 : 2 : join_plan->joinqual = list_delete(join_plan->joinqual,
1389 : : qual);
1390 : : }
1391 : : }
1392 : :
1393 : : /*
1394 : : * Now fix the subplan's tlist --- this might result in inserting
1395 : : * a Result node atop the plan tree.
1396 : : */
1397 : 24 : outer_plan = change_plan_targetlist(outer_plan, fdw_scan_tlist,
1398 : 24 : best_path->path.parallel_safe);
1399 : : }
1400 : : }
1401 : :
1402 : : /*
1403 : : * Build the query string to be sent for execution, and identify
1404 : : * expressions to be sent as parameters.
1405 : : */
4552 1406 : 996 : initStringInfo(&sql);
3497 rhaas@postgresql.org 1407 : 996 : deparseSelectStmtForRel(&sql, root, foreignrel, fdw_scan_tlist,
1408 : : remote_exprs, best_path->path.pathkeys,
1409 : : has_final_sort, has_limit, false,
1410 : : &retrieved_attrs, ¶ms_list);
1411 : :
1412 : : /* Remember remote_exprs for possible use by postgresPlanDirectModify */
3070 tgl@sss.pgh.pa.us 1413 : 996 : fpinfo->final_remote_exprs = remote_exprs;
1414 : :
1415 : : /*
1416 : : * Build the fdw_private list that will be available to the executor.
1417 : : * Items in the list must match order in enum FdwScanPrivateIndex.
1418 : : */
1419 : 996 : fdw_private = list_make3(makeString(sql.data),
1420 : : retrieved_attrs,
1421 : : makeInteger(fpinfo->fetch_size));
3078 rhaas@postgresql.org 1422 [ + + + + : 996 : if (IS_JOIN_REL(foreignrel) || IS_UPPER_REL(foreignrel))
+ + + + ]
3497 1423 : 281 : fdw_private = lappend(fdw_private,
2105 tgl@sss.pgh.pa.us 1424 : 281 : makeString(fpinfo->relation_name));
1425 : :
1426 : : /*
1427 : : * Create the ForeignScan node for the given relation.
1428 : : *
1429 : : * Note that the remote parameter expressions are stored in the fdw_exprs
1430 : : * field of the finished plan node; we can't keep them in private state
1431 : : * because then they wouldn't be subject to later planner processing.
1432 : : */
4580 1433 : 996 : return make_foreignscan(tlist,
1434 : : local_exprs,
1435 : : scan_relid,
1436 : : params_list,
1437 : : fdw_private,
1438 : : fdw_scan_tlist,
1439 : : fdw_recheck_quals,
1440 : : outer_plan);
1441 : : }
1442 : :
1443 : : /*
1444 : : * Construct a tuple descriptor for the scan tuples handled by a foreign join.
1445 : : */
1446 : : static TupleDesc
1555 1447 : 160 : get_tupdesc_for_join_scan_tuples(ForeignScanState *node)
1448 : : {
1449 : 160 : ForeignScan *fsplan = (ForeignScan *) node->ss.ps.plan;
1450 : 160 : EState *estate = node->ss.ps.state;
1451 : : TupleDesc tupdesc;
1452 : :
1453 : : /*
1454 : : * The core code has already set up a scan tuple slot based on
1455 : : * fsplan->fdw_scan_tlist, and this slot's tupdesc is mostly good enough,
1456 : : * but there's one case where it isn't. If we have any whole-row row
1457 : : * identifier Vars, they may have vartype RECORD, and we need to replace
1458 : : * that with the associated table's actual composite type. This ensures
1459 : : * that when we read those ROW() expression values from the remote server,
1460 : : * we can convert them to a composite type the local server knows.
1461 : : */
1462 : 160 : tupdesc = CreateTupleDescCopy(node->ss.ss_ScanTupleSlot->tts_tupleDescriptor);
1463 [ + + ]: 673 : for (int i = 0; i < tupdesc->natts; i++)
1464 : : {
1465 : 513 : Form_pg_attribute att = TupleDescAttr(tupdesc, i);
1466 : : Var *var;
1467 : : RangeTblEntry *rte;
1468 : : Oid reltype;
1469 : :
1470 : : /* Nothing to do if it's not a generic RECORD attribute */
1471 [ + + - + ]: 513 : if (att->atttypid != RECORDOID || att->atttypmod >= 0)
1472 : 510 : continue;
1473 : :
1474 : : /*
1475 : : * If we can't identify the referenced table, do nothing. This'll
1476 : : * likely lead to failure later, but perhaps we can muddle through.
1477 : : */
1478 : 3 : var = (Var *) list_nth_node(TargetEntry, fsplan->fdw_scan_tlist,
1479 : : i)->expr;
1480 [ + - - + ]: 3 : if (!IsA(var, Var) || var->varattno != 0)
1555 tgl@sss.pgh.pa.us 1481 :UBC 0 : continue;
1555 tgl@sss.pgh.pa.us 1482 :CBC 3 : rte = list_nth(estate->es_range_table, var->varno - 1);
1483 [ - + ]: 3 : if (rte->rtekind != RTE_RELATION)
1555 tgl@sss.pgh.pa.us 1484 :UBC 0 : continue;
1555 tgl@sss.pgh.pa.us 1485 :CBC 3 : reltype = get_rel_type_id(rte->relid);
1486 [ - + ]: 3 : if (!OidIsValid(reltype))
1555 tgl@sss.pgh.pa.us 1487 :UBC 0 : continue;
1555 tgl@sss.pgh.pa.us 1488 :CBC 3 : att->atttypid = reltype;
1489 : : /* shouldn't need to change anything else */
1490 : : }
1491 : 160 : return tupdesc;
1492 : : }
1493 : :
1494 : : /*
1495 : : * postgresBeginForeignScan
1496 : : * Initiate an executor scan of a foreign PostgreSQL table.
1497 : : */
1498 : : static void
4580 1499 : 884 : postgresBeginForeignScan(ForeignScanState *node, int eflags)
1500 : : {
1501 : 884 : ForeignScan *fsplan = (ForeignScan *) node->ss.ps.plan;
1502 : 884 : EState *estate = node->ss.ps.state;
1503 : : PgFdwScanState *fsstate;
1504 : : RangeTblEntry *rte;
1505 : : Oid userid;
1506 : : ForeignTable *table;
1507 : : UserMapping *user;
1508 : : int rtindex;
1509 : : int numParams;
1510 : :
1511 : : /*
1512 : : * Do nothing in EXPLAIN (no ANALYZE) case. node->fdw_state stays NULL.
1513 : : */
1514 [ + + ]: 884 : if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
1515 : 380 : return;
1516 : :
1517 : : /*
1518 : : * We'll save private state in node->fdw_state.
1519 : : */
4563 1520 : 504 : fsstate = (PgFdwScanState *) palloc0(sizeof(PgFdwScanState));
282 peter@eisentraut.org 1521 : 504 : node->fdw_state = fsstate;
1522 : :
1523 : : /*
1524 : : * Identify which user to do the remote access as. This should match what
1525 : : * ExecCheckPermissions() does.
1526 : : */
1011 alvherre@alvh.no-ip. 1527 [ + + ]: 504 : userid = OidIsValid(fsplan->checkAsUser) ? fsplan->checkAsUser : GetUserId();
3497 rhaas@postgresql.org 1528 [ + + ]: 504 : if (fsplan->scan.scanrelid > 0)
3340 tgl@sss.pgh.pa.us 1529 : 345 : rtindex = fsplan->scan.scanrelid;
1530 : : else
950 1531 : 159 : rtindex = bms_next_member(fsplan->fs_base_relids, -1);
2529 1532 : 504 : rte = exec_rt_fetch(rtindex, estate);
1533 : :
1534 : : /* Get info about foreign table. */
3340 1535 : 504 : table = GetForeignTable(rte->relid);
1536 : 504 : user = GetUserMapping(userid, table->serverid);
1537 : :
1538 : : /*
1539 : : * Get connection to the foreign server. Connection manager will
1540 : : * establish new connection if necessary.
1541 : : */
1620 efujita@postgresql.o 1542 : 504 : fsstate->conn = GetConnection(user, false, &fsstate->conn_state);
1543 : :
1544 : : /* Assign a unique ID for my cursor */
4563 tgl@sss.pgh.pa.us 1545 : 494 : fsstate->cursor_number = GetCursorNumber(fsstate->conn);
1546 : 494 : fsstate->cursor_exists = false;
1547 : :
1548 : : /* Get private info created by planner functions. */
4551 1549 : 494 : fsstate->query = strVal(list_nth(fsplan->fdw_private,
1550 : : FdwScanPrivateSelectSql));
1551 : 494 : fsstate->retrieved_attrs = (List *) list_nth(fsplan->fdw_private,
1552 : : FdwScanPrivateRetrievedAttrs);
3503 rhaas@postgresql.org 1553 : 494 : fsstate->fetch_size = intVal(list_nth(fsplan->fdw_private,
1554 : : FdwScanPrivateFetchSize));
1555 : :
1556 : : /* Create contexts for batches of tuples and per-tuple temp workspace. */
4563 tgl@sss.pgh.pa.us 1557 : 494 : fsstate->batch_cxt = AllocSetContextCreate(estate->es_query_cxt,
1558 : : "postgres_fdw tuple data",
1559 : : ALLOCSET_DEFAULT_SIZES);
1560 : 494 : fsstate->temp_cxt = AllocSetContextCreate(estate->es_query_cxt,
1561 : : "postgres_fdw temporary data",
1562 : : ALLOCSET_SMALL_SIZES);
1563 : :
1564 : : /*
1565 : : * Get info we'll need for converting data fetched from the foreign server
1566 : : * into local representation and error reporting during that process.
1567 : : */
3497 rhaas@postgresql.org 1568 [ + + ]: 494 : if (fsplan->scan.scanrelid > 0)
1569 : : {
3340 tgl@sss.pgh.pa.us 1570 : 335 : fsstate->rel = node->ss.ss_currentRelation;
3497 rhaas@postgresql.org 1571 : 335 : fsstate->tupdesc = RelationGetDescr(fsstate->rel);
1572 : : }
1573 : : else
1574 : : {
3340 tgl@sss.pgh.pa.us 1575 : 159 : fsstate->rel = NULL;
1555 1576 : 159 : fsstate->tupdesc = get_tupdesc_for_join_scan_tuples(node);
1577 : : }
1578 : :
3497 rhaas@postgresql.org 1579 : 494 : fsstate->attinmeta = TupleDescGetAttInMetadata(fsstate->tupdesc);
1580 : :
1581 : : /*
1582 : : * Prepare for processing of parameters used in remote query, if any.
1583 : : */
3459 1584 : 494 : numParams = list_length(fsplan->fdw_exprs);
1585 : 494 : fsstate->numParams = numParams;
4580 tgl@sss.pgh.pa.us 1586 [ + + ]: 494 : if (numParams > 0)
3459 rhaas@postgresql.org 1587 : 19 : prepare_query_params((PlanState *) node,
1588 : : fsplan->fdw_exprs,
1589 : : numParams,
1590 : : &fsstate->param_flinfo,
1591 : : &fsstate->param_exprs,
1592 : : &fsstate->param_values);
1593 : :
1594 : : /* Set the async-capable flag */
1578 efujita@postgresql.o 1595 : 494 : fsstate->async_capable = node->ss.ps.async_capable;
1596 : : }
1597 : :
1598 : : /*
1599 : : * postgresIterateForeignScan
1600 : : * Retrieve next row from the result set, or clear tuple slot to indicate
1601 : : * EOF.
1602 : : */
1603 : : static TupleTableSlot *
4580 tgl@sss.pgh.pa.us 1604 : 70886 : postgresIterateForeignScan(ForeignScanState *node)
1605 : : {
4563 1606 : 70886 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
4580 1607 : 70886 : TupleTableSlot *slot = node->ss.ss_ScanTupleSlot;
1608 : :
1609 : : /*
1610 : : * In sync mode, if this is the first call after Begin or ReScan, we need
1611 : : * to create the cursor on the remote side. In async mode, we would have
1612 : : * already created the cursor before we get here, even if this is the
1613 : : * first call after Begin or ReScan.
1614 : : */
4563 1615 [ + + ]: 70886 : if (!fsstate->cursor_exists)
4580 1616 : 761 : create_cursor(node);
1617 : :
1618 : : /*
1619 : : * Get some more tuples, if we've run out.
1620 : : */
4563 1621 [ + + ]: 70884 : if (fsstate->next_tuple >= fsstate->num_tuples)
1622 : : {
1623 : : /* In async mode, just clear tuple slot. */
1620 efujita@postgresql.o 1624 [ + + ]: 2042 : if (fsstate->async_capable)
1625 : 32 : return ExecClearTuple(slot);
1626 : : /* No point in another fetch if we already detected EOF, though. */
4563 tgl@sss.pgh.pa.us 1627 [ + + ]: 2010 : if (!fsstate->eof_reached)
4580 1628 : 1339 : fetch_more_data(node);
1629 : : /* If we didn't get any tuples, must be end of data. */
4563 1630 [ + + ]: 2004 : if (fsstate->next_tuple >= fsstate->num_tuples)
4580 1631 : 741 : return ExecClearTuple(slot);
1632 : : }
1633 : :
1634 : : /*
1635 : : * Return the next tuple.
1636 : : */
2538 andres@anarazel.de 1637 : 70105 : ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++],
1638 : : slot,
1639 : : false);
1640 : :
4580 tgl@sss.pgh.pa.us 1641 : 70105 : return slot;
1642 : : }
1643 : :
1644 : : /*
1645 : : * postgresReScanForeignScan
1646 : : * Restart the scan.
1647 : : */
1648 : : static void
1649 : 401 : postgresReScanForeignScan(ForeignScanState *node)
1650 : : {
4563 1651 : 401 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
1652 : : char sql[64];
1653 : : PGresult *res;
1654 : :
1655 : : /* If we haven't created the cursor yet, nothing to do. */
1656 [ + + ]: 401 : if (!fsstate->cursor_exists)
4580 1657 : 44 : return;
1658 : :
1659 : : /*
1660 : : * If the node is async-capable, and an asynchronous fetch for it has
1661 : : * begun, the asynchronous fetch might not have yet completed. Check if
1662 : : * the node is async-capable, and an asynchronous fetch for it is still in
1663 : : * progress; if so, complete the asynchronous fetch before restarting the
1664 : : * scan.
1665 : : */
1318 efujita@postgresql.o 1666 [ + + ]: 369 : if (fsstate->async_capable &&
1667 [ + + ]: 21 : fsstate->conn_state->pendingAreq &&
1668 [ + + ]: 2 : fsstate->conn_state->pendingAreq->requestee == (PlanState *) node)
1669 : 1 : fetch_more_data(node);
1670 : :
1671 : : /*
1672 : : * If any internal parameters affecting this node have changed, we'd
1673 : : * better destroy and recreate the cursor. Otherwise, if the remote
1674 : : * server is v14 or older, rewinding it should be good enough; if not,
1675 : : * rewind is only allowed for scrollable cursors, but we don't have a way
1676 : : * to check the scrollability of it, so destroy and recreate it in any
1677 : : * case. If we've only fetched zero or one batch, we needn't even rewind
1678 : : * the cursor, just rescan what we have.
1679 : : */
4580 tgl@sss.pgh.pa.us 1680 [ + + ]: 369 : if (node->ss.ps.chgParam != NULL)
1681 : : {
4563 1682 : 338 : fsstate->cursor_exists = false;
4580 1683 : 338 : snprintf(sql, sizeof(sql), "CLOSE c%u",
1684 : : fsstate->cursor_number);
1685 : : }
4563 1686 [ + + ]: 31 : else if (fsstate->fetch_ct_2 > 1)
1687 : : {
414 efujita@postgresql.o 1688 [ - + ]: 19 : if (PQserverVersion(fsstate->conn) < 150000)
414 efujita@postgresql.o 1689 :UBC 0 : snprintf(sql, sizeof(sql), "MOVE BACKWARD ALL IN c%u",
1690 : : fsstate->cursor_number);
1691 : : else
1692 : : {
414 efujita@postgresql.o 1693 :CBC 19 : fsstate->cursor_exists = false;
1694 : 19 : snprintf(sql, sizeof(sql), "CLOSE c%u",
1695 : : fsstate->cursor_number);
1696 : : }
1697 : : }
1698 : : else
1699 : : {
1700 : : /* Easy: just rescan what we already have in memory, if anything */
4563 tgl@sss.pgh.pa.us 1701 : 12 : fsstate->next_tuple = 0;
4580 1702 : 12 : return;
1703 : : }
1704 : :
1620 efujita@postgresql.o 1705 : 357 : res = pgfdw_exec_query(fsstate->conn, sql, fsstate->conn_state);
4580 tgl@sss.pgh.pa.us 1706 [ - + ]: 357 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 1707 :UNC 0 : pgfdw_report_error(res, fsstate->conn, sql);
4580 tgl@sss.pgh.pa.us 1708 :CBC 357 : PQclear(res);
1709 : :
1710 : : /* Now force a fresh FETCH. */
4563 1711 : 357 : fsstate->tuples = NULL;
1712 : 357 : fsstate->num_tuples = 0;
1713 : 357 : fsstate->next_tuple = 0;
1714 : 357 : fsstate->fetch_ct_2 = 0;
1715 : 357 : fsstate->eof_reached = false;
1716 : : }
1717 : :
1718 : : /*
1719 : : * postgresEndForeignScan
1720 : : * Finish scanning foreign table and dispose objects used for this scan
1721 : : */
1722 : : static void
4580 1723 : 853 : postgresEndForeignScan(ForeignScanState *node)
1724 : : {
4563 1725 : 853 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
1726 : :
1727 : : /* if fsstate is NULL, we are in EXPLAIN; nothing to do */
1728 [ + + ]: 853 : if (fsstate == NULL)
4580 1729 : 380 : return;
1730 : :
1731 : : /* Close the cursor if open, to prevent accumulation of cursors */
4563 1732 [ + + ]: 473 : if (fsstate->cursor_exists)
1620 efujita@postgresql.o 1733 : 452 : close_cursor(fsstate->conn, fsstate->cursor_number,
1734 : : fsstate->conn_state);
1735 : :
1736 : : /* Release remote connection */
4563 tgl@sss.pgh.pa.us 1737 : 473 : ReleaseConnection(fsstate->conn);
1738 : 473 : fsstate->conn = NULL;
1739 : :
1740 : : /* MemoryContexts will be deleted automatically. */
1741 : : }
1742 : :
1743 : : /*
1744 : : * postgresAddForeignUpdateTargets
1745 : : * Add resjunk column(s) needed for update/delete on a foreign table
1746 : : */
1747 : : static void
1620 1748 : 189 : postgresAddForeignUpdateTargets(PlannerInfo *root,
1749 : : Index rtindex,
1750 : : RangeTblEntry *target_rte,
1751 : : Relation target_relation)
1752 : : {
1753 : : Var *var;
1754 : :
1755 : : /*
1756 : : * In postgres_fdw, what we need is the ctid, same as for a regular table.
1757 : : */
1758 : :
1759 : : /* Make a Var representing the desired value */
1760 : 189 : var = makeVar(rtindex,
1761 : : SelfItemPointerAttributeNumber,
1762 : : TIDOID,
1763 : : -1,
1764 : : InvalidOid,
1765 : : 0);
1766 : :
1767 : : /* Register it as a row-identity column needed by this target rel */
1768 : 189 : add_row_identity_var(root, var, rtindex, "ctid");
4563 1769 : 189 : }
1770 : :
1771 : : /*
1772 : : * postgresPlanForeignModify
1773 : : * Plan an insert/update/delete operation on a foreign table
1774 : : */
1775 : : static List *
1776 : 170 : postgresPlanForeignModify(PlannerInfo *root,
1777 : : ModifyTable *plan,
1778 : : Index resultRelation,
1779 : : int subplan_index)
1780 : : {
1781 : 170 : CmdType operation = plan->operation;
4561 1782 [ + - ]: 170 : RangeTblEntry *rte = planner_rt_fetch(resultRelation, root);
1783 : : Relation rel;
1784 : : StringInfoData sql;
4563 1785 : 170 : List *targetAttrs = NIL;
2617 jdavis@postgresql.or 1786 : 170 : List *withCheckOptionList = NIL;
4563 tgl@sss.pgh.pa.us 1787 : 170 : List *returningList = NIL;
4551 1788 : 170 : List *retrieved_attrs = NIL;
3774 andres@anarazel.de 1789 : 170 : bool doNothing = false;
1690 tomas.vondra@postgre 1790 : 170 : int values_end_len = -1;
1791 : :
4563 tgl@sss.pgh.pa.us 1792 : 170 : initStringInfo(&sql);
1793 : :
1794 : : /*
1795 : : * Core code already has some lock on each rel being planned, so we can
1796 : : * use NoLock here.
1797 : : */
2420 andres@anarazel.de 1798 : 170 : rel = table_open(rte->relid, NoLock);
1799 : :
1800 : : /*
1801 : : * In an INSERT, we transmit all columns that are defined in the foreign
1802 : : * table. In an UPDATE, if there are BEFORE ROW UPDATE triggers on the
1803 : : * foreign table, we transmit all columns like INSERT; else we transmit
1804 : : * only columns that were explicitly targets of the UPDATE, so as to avoid
1805 : : * unnecessary data transmission. (We can't do that for INSERT since we
1806 : : * would miss sending default values for columns not listed in the source
1807 : : * statement, and for UPDATE if there are BEFORE ROW UPDATE triggers since
1808 : : * those triggers might change values for non-target columns, in which
1809 : : * case we would miss sending changed values for those columns.)
1810 : : */
2277 efujita@postgresql.o 1811 [ + + + + ]: 170 : if (operation == CMD_INSERT ||
1812 : 60 : (operation == CMD_UPDATE &&
1813 [ + + ]: 60 : rel->trigdesc &&
1814 [ + + ]: 18 : rel->trigdesc->trig_update_before_row))
4561 tgl@sss.pgh.pa.us 1815 : 103 : {
1816 : 103 : TupleDesc tupdesc = RelationGetDescr(rel);
1817 : : int attnum;
1818 : :
1819 [ + + ]: 434 : for (attnum = 1; attnum <= tupdesc->natts; attnum++)
1820 : : {
260 drowley@postgresql.o 1821 : 331 : CompactAttribute *attr = TupleDescCompactAttr(tupdesc, attnum - 1);
1822 : :
4561 tgl@sss.pgh.pa.us 1823 [ + + ]: 331 : if (!attr->attisdropped)
1824 : 314 : targetAttrs = lappend_int(targetAttrs, attnum);
1825 : : }
1826 : : }
1827 [ + + ]: 67 : else if (operation == CMD_UPDATE)
1828 : : {
1829 : : int col;
1005 alvherre@alvh.no-ip. 1830 : 45 : RelOptInfo *rel = find_base_rel(root, resultRelation);
1831 : 45 : Bitmapset *allUpdatedCols = get_rel_all_updated_cols(root, rel);
1832 : :
3935 tgl@sss.pgh.pa.us 1833 : 45 : col = -1;
2352 peter@eisentraut.org 1834 [ + + ]: 100 : while ((col = bms_next_member(allUpdatedCols, col)) >= 0)
1835 : : {
1836 : : /* bit numbers are offset by FirstLowInvalidHeapAttributeNumber */
3935 tgl@sss.pgh.pa.us 1837 : 55 : AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
1838 : :
2999 1839 [ - + ]: 55 : if (attno <= InvalidAttrNumber) /* shouldn't happen */
4563 tgl@sss.pgh.pa.us 1840 [ # # ]:UBC 0 : elog(ERROR, "system-column update is not supported");
3935 tgl@sss.pgh.pa.us 1841 :CBC 55 : targetAttrs = lappend_int(targetAttrs, attno);
1842 : : }
1843 : : }
1844 : :
1845 : : /*
1846 : : * Extract the relevant WITH CHECK OPTION list if any.
1847 : : */
2617 jdavis@postgresql.or 1848 [ + + ]: 170 : if (plan->withCheckOptionLists)
1849 : 16 : withCheckOptionList = (List *) list_nth(plan->withCheckOptionLists,
1850 : : subplan_index);
1851 : :
1852 : : /*
1853 : : * Extract the relevant RETURNING list if any.
1854 : : */
4563 tgl@sss.pgh.pa.us 1855 [ + + ]: 170 : if (plan->returningLists)
1856 : 32 : returningList = (List *) list_nth(plan->returningLists, subplan_index);
1857 : :
1858 : : /*
1859 : : * ON CONFLICT DO UPDATE and DO NOTHING case with inference specification
1860 : : * should have already been rejected in the optimizer, as presently there
1861 : : * is no way to recognize an arbiter index on a foreign table. Only DO
1862 : : * NOTHING is supported without an inference specification.
1863 : : */
3774 andres@anarazel.de 1864 [ + + ]: 170 : if (plan->onConflictAction == ONCONFLICT_NOTHING)
1865 : 1 : doNothing = true;
1866 [ - + ]: 169 : else if (plan->onConflictAction != ONCONFLICT_NONE)
3774 andres@anarazel.de 1867 [ # # ]:UBC 0 : elog(ERROR, "unexpected ON CONFLICT specification: %d",
1868 : : (int) plan->onConflictAction);
1869 : :
1870 : : /*
1871 : : * Construct the SQL command string.
1872 : : */
4563 tgl@sss.pgh.pa.us 1873 [ + + + - ]:CBC 170 : switch (operation)
1874 : : {
1875 : 88 : case CMD_INSERT:
2685 rhaas@postgresql.org 1876 : 88 : deparseInsertSql(&sql, rte, resultRelation, rel,
1877 : : targetAttrs, doNothing,
1878 : : withCheckOptionList, returningList,
1879 : : &retrieved_attrs, &values_end_len);
4563 tgl@sss.pgh.pa.us 1880 : 88 : break;
1881 : 60 : case CMD_UPDATE:
2685 rhaas@postgresql.org 1882 : 60 : deparseUpdateSql(&sql, rte, resultRelation, rel,
1883 : : targetAttrs,
1884 : : withCheckOptionList, returningList,
1885 : : &retrieved_attrs);
4563 tgl@sss.pgh.pa.us 1886 : 60 : break;
1887 : 22 : case CMD_DELETE:
2685 rhaas@postgresql.org 1888 : 22 : deparseDeleteSql(&sql, rte, resultRelation, rel,
1889 : : returningList,
1890 : : &retrieved_attrs);
4563 tgl@sss.pgh.pa.us 1891 : 22 : break;
4563 tgl@sss.pgh.pa.us 1892 :UBC 0 : default:
1893 [ # # ]: 0 : elog(ERROR, "unexpected operation: %d", (int) operation);
1894 : : break;
1895 : : }
1896 : :
2420 andres@anarazel.de 1897 :CBC 170 : table_close(rel, NoLock);
1898 : :
1899 : : /*
1900 : : * Build the fdw_private list that will be available to the executor.
1901 : : * Items in the list must match enum FdwModifyPrivateIndex, above.
1902 : : */
1690 tomas.vondra@postgre 1903 : 170 : return list_make5(makeString(sql.data),
1904 : : targetAttrs,
1905 : : makeInteger(values_end_len),
1906 : : makeBoolean((retrieved_attrs != NIL)),
1907 : : retrieved_attrs);
1908 : : }
1909 : :
1910 : : /*
1911 : : * postgresBeginForeignModify
1912 : : * Begin an insert/update/delete operation on a foreign table
1913 : : */
1914 : : static void
4563 tgl@sss.pgh.pa.us 1915 : 170 : postgresBeginForeignModify(ModifyTableState *mtstate,
1916 : : ResultRelInfo *resultRelInfo,
1917 : : List *fdw_private,
1918 : : int subplan_index,
1919 : : int eflags)
1920 : : {
1921 : : PgFdwModifyState *fmstate;
1922 : : char *query;
1923 : : List *target_attrs;
1924 : : bool has_returning;
1925 : : int values_end_len;
1926 : : List *retrieved_attrs;
1927 : : RangeTblEntry *rte;
1928 : :
1929 : : /*
1930 : : * Do nothing in EXPLAIN (no ANALYZE) case. resultRelInfo->ri_FdwState
1931 : : * stays NULL.
1932 : : */
1933 [ + + ]: 170 : if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
1934 : 46 : return;
1935 : :
1936 : : /* Deconstruct fdw_private data. */
2710 rhaas@postgresql.org 1937 : 124 : query = strVal(list_nth(fdw_private,
1938 : : FdwModifyPrivateUpdateSql));
1939 : 124 : target_attrs = (List *) list_nth(fdw_private,
1940 : : FdwModifyPrivateTargetAttnums);
1690 tomas.vondra@postgre 1941 : 124 : values_end_len = intVal(list_nth(fdw_private,
1942 : : FdwModifyPrivateLen));
1331 peter@eisentraut.org 1943 : 124 : has_returning = boolVal(list_nth(fdw_private,
1944 : : FdwModifyPrivateHasReturning));
2710 rhaas@postgresql.org 1945 : 124 : retrieved_attrs = (List *) list_nth(fdw_private,
1946 : : FdwModifyPrivateRetrievedAttrs);
1947 : :
1948 : : /* Find RTE. */
2529 tgl@sss.pgh.pa.us 1949 : 124 : rte = exec_rt_fetch(resultRelInfo->ri_RangeTableIndex,
1950 : : mtstate->ps.state);
1951 : :
1952 : : /* Construct an execution state. */
2710 rhaas@postgresql.org 1953 : 124 : fmstate = create_foreign_modify(mtstate->ps.state,
1954 : : rte,
1955 : : resultRelInfo,
1956 : : mtstate->operation,
1620 tgl@sss.pgh.pa.us 1957 : 124 : outerPlanState(mtstate)->plan,
1958 : : query,
1959 : : target_attrs,
1960 : : values_end_len,
1961 : : has_returning,
1962 : : retrieved_attrs);
1963 : :
4563 1964 : 124 : resultRelInfo->ri_FdwState = fmstate;
1965 : : }
1966 : :
1967 : : /*
1968 : : * postgresExecForeignInsert
1969 : : * Insert one row into a foreign table
1970 : : */
1971 : : static TupleTableSlot *
1972 : 892 : postgresExecForeignInsert(EState *estate,
1973 : : ResultRelInfo *resultRelInfo,
1974 : : TupleTableSlot *slot,
1975 : : TupleTableSlot *planSlot)
1976 : : {
2327 efujita@postgresql.o 1977 : 892 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
1978 : : TupleTableSlot **rslot;
1578 tgl@sss.pgh.pa.us 1979 : 892 : int numSlots = 1;
1980 : :
1981 : : /*
1982 : : * If the fmstate has aux_fmstate set, use the aux_fmstate (see
1983 : : * postgresBeginForeignInsert())
1984 : : */
1690 tomas.vondra@postgre 1985 [ - + ]: 892 : if (fmstate->aux_fmstate)
1690 tomas.vondra@postgre 1986 :UBC 0 : resultRelInfo->ri_FdwState = fmstate->aux_fmstate;
1690 tomas.vondra@postgre 1987 :CBC 892 : rslot = execute_foreign_modify(estate, resultRelInfo, CMD_INSERT,
1988 : : &slot, &planSlot, &numSlots);
1989 : : /* Revert that change */
1990 [ - + ]: 888 : if (fmstate->aux_fmstate)
1690 tomas.vondra@postgre 1991 :UBC 0 : resultRelInfo->ri_FdwState = fmstate;
1992 : :
1690 tomas.vondra@postgre 1993 [ + + ]:CBC 888 : return rslot ? *rslot : NULL;
1994 : : }
1995 : :
1996 : : /*
1997 : : * postgresExecForeignBatchInsert
1998 : : * Insert multiple rows into a foreign table
1999 : : */
2000 : : static TupleTableSlot **
2001 : 42 : postgresExecForeignBatchInsert(EState *estate,
2002 : : ResultRelInfo *resultRelInfo,
2003 : : TupleTableSlot **slots,
2004 : : TupleTableSlot **planSlots,
2005 : : int *numSlots)
2006 : : {
2007 : 42 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
2008 : : TupleTableSlot **rslot;
2009 : :
2010 : : /*
2011 : : * If the fmstate has aux_fmstate set, use the aux_fmstate (see
2012 : : * postgresBeginForeignInsert())
2013 : : */
2327 efujita@postgresql.o 2014 [ - + ]: 42 : if (fmstate->aux_fmstate)
2327 efujita@postgresql.o 2015 :UBC 0 : resultRelInfo->ri_FdwState = fmstate->aux_fmstate;
2327 efujita@postgresql.o 2016 :CBC 42 : rslot = execute_foreign_modify(estate, resultRelInfo, CMD_INSERT,
2017 : : slots, planSlots, numSlots);
2018 : : /* Revert that change */
2019 [ - + ]: 41 : if (fmstate->aux_fmstate)
2327 efujita@postgresql.o 2020 :UBC 0 : resultRelInfo->ri_FdwState = fmstate;
2021 : :
2327 efujita@postgresql.o 2022 :CBC 41 : return rslot;
2023 : : }
2024 : :
2025 : : /*
2026 : : * postgresGetForeignModifyBatchSize
2027 : : * Determine the maximum number of tuples that can be inserted in bulk
2028 : : *
2029 : : * Returns the batch size specified for server or table. When batching is not
2030 : : * allowed (e.g. for tables with BEFORE/AFTER ROW triggers or with RETURNING
2031 : : * clause), returns 1.
2032 : : */
2033 : : static int
1690 tomas.vondra@postgre 2034 : 146 : postgresGetForeignModifyBatchSize(ResultRelInfo *resultRelInfo)
2035 : : {
2036 : : int batch_size;
991 efujita@postgresql.o 2037 : 146 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
2038 : :
2039 : : /* should be called only once */
1690 tomas.vondra@postgre 2040 [ - + ]: 146 : Assert(resultRelInfo->ri_BatchSize == 0);
2041 : :
2042 : : /*
2043 : : * Should never get called when the insert is being performed on a table
2044 : : * that is also among the target relations of an UPDATE operation, because
2045 : : * postgresBeginForeignInsert() currently rejects such insert attempts.
2046 : : */
1661 2047 [ + + - + ]: 146 : Assert(fmstate == NULL || fmstate->aux_fmstate == NULL);
2048 : :
2049 : : /*
2050 : : * In EXPLAIN without ANALYZE, ri_FdwState is NULL, so we have to lookup
2051 : : * the option directly in server/table options. Otherwise just use the
2052 : : * value we determined earlier.
2053 : : */
2054 [ + + ]: 146 : if (fmstate)
2055 : 133 : batch_size = fmstate->batch_size;
2056 : : else
1690 2057 : 13 : batch_size = get_batch_size_option(resultRelInfo->ri_RelationDesc);
2058 : :
2059 : : /*
2060 : : * Disable batching when we have to use RETURNING, there are any
2061 : : * BEFORE/AFTER ROW INSERT triggers on the foreign table, or there are any
2062 : : * WITH CHECK OPTION constraints from parent views.
2063 : : *
2064 : : * When there are any BEFORE ROW INSERT triggers on the table, we can't
2065 : : * support it, because such triggers might query the table we're inserting
2066 : : * into and act differently if the tuples that have already been processed
2067 : : * and prepared for insertion are not there.
2068 : : */
2069 [ + + ]: 146 : if (resultRelInfo->ri_projectReturning != NULL ||
1128 efujita@postgresql.o 2070 [ + + ]: 125 : resultRelInfo->ri_WithCheckOptions != NIL ||
1690 tomas.vondra@postgre 2071 [ + + ]: 116 : (resultRelInfo->ri_TrigDesc &&
1234 efujita@postgresql.o 2072 [ + + ]: 14 : (resultRelInfo->ri_TrigDesc->trig_insert_before_row ||
2073 [ + - ]: 1 : resultRelInfo->ri_TrigDesc->trig_insert_after_row)))
1690 tomas.vondra@postgre 2074 : 44 : return 1;
2075 : :
2076 : : /*
2077 : : * If the foreign table has no columns, disable batching as the INSERT
2078 : : * syntax doesn't allow batching multiple empty rows into a zero-column
2079 : : * table in a single statement. This is needed for COPY FROM, in which
2080 : : * case fmstate must be non-NULL.
2081 : : */
1059 efujita@postgresql.o 2082 [ + + + + ]: 102 : if (fmstate && list_length(fmstate->target_attrs) == 0)
2083 : 1 : return 1;
2084 : :
2085 : : /*
2086 : : * Otherwise use the batch size specified for server/table. The number of
2087 : : * parameters in a batch is limited to 65535 (uint16), so make sure we
2088 : : * don't exceed this limit by using the maximum batch_size possible.
2089 : : */
1551 tomas.vondra@postgre 2090 [ + + + - ]: 101 : if (fmstate && fmstate->p_nums > 0)
2091 : 93 : batch_size = Min(batch_size, PQ_QUERY_PARAM_MAX_LIMIT / fmstate->p_nums);
2092 : :
1690 2093 : 101 : return batch_size;
2094 : : }
2095 : :
2096 : : /*
2097 : : * postgresExecForeignUpdate
2098 : : * Update one row in a foreign table
2099 : : */
2100 : : static TupleTableSlot *
4563 tgl@sss.pgh.pa.us 2101 : 95 : postgresExecForeignUpdate(EState *estate,
2102 : : ResultRelInfo *resultRelInfo,
2103 : : TupleTableSlot *slot,
2104 : : TupleTableSlot *planSlot)
2105 : : {
2106 : : TupleTableSlot **rslot;
1578 2107 : 95 : int numSlots = 1;
2108 : :
1690 tomas.vondra@postgre 2109 : 95 : rslot = execute_foreign_modify(estate, resultRelInfo, CMD_UPDATE,
2110 : : &slot, &planSlot, &numSlots);
2111 : :
2112 [ + + ]: 95 : return rslot ? rslot[0] : NULL;
2113 : : }
2114 : :
2115 : : /*
2116 : : * postgresExecForeignDelete
2117 : : * Delete one row from a foreign table
2118 : : */
2119 : : static TupleTableSlot *
4563 tgl@sss.pgh.pa.us 2120 : 23 : postgresExecForeignDelete(EState *estate,
2121 : : ResultRelInfo *resultRelInfo,
2122 : : TupleTableSlot *slot,
2123 : : TupleTableSlot *planSlot)
2124 : : {
2125 : : TupleTableSlot **rslot;
1578 2126 : 23 : int numSlots = 1;
2127 : :
1690 tomas.vondra@postgre 2128 : 23 : rslot = execute_foreign_modify(estate, resultRelInfo, CMD_DELETE,
2129 : : &slot, &planSlot, &numSlots);
2130 : :
2131 [ + - ]: 23 : return rslot ? rslot[0] : NULL;
2132 : : }
2133 : :
2134 : : /*
2135 : : * postgresEndForeignModify
2136 : : * Finish an insert/update/delete operation on a foreign table
2137 : : */
2138 : : static void
4563 tgl@sss.pgh.pa.us 2139 : 156 : postgresEndForeignModify(EState *estate,
2140 : : ResultRelInfo *resultRelInfo)
2141 : : {
2142 : 156 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
2143 : :
2144 : : /* If fmstate is NULL, we are in EXPLAIN; nothing to do */
2145 [ + + ]: 156 : if (fmstate == NULL)
2146 : 46 : return;
2147 : :
2148 : : /* Destroy the execution state */
2710 rhaas@postgresql.org 2149 : 110 : finish_foreign_modify(fmstate);
2150 : : }
2151 : :
2152 : : /*
2153 : : * postgresBeginForeignInsert
2154 : : * Begin an insert operation on a foreign table
2155 : : */
2156 : : static void
2157 : 64 : postgresBeginForeignInsert(ModifyTableState *mtstate,
2158 : : ResultRelInfo *resultRelInfo)
2159 : : {
2160 : : PgFdwModifyState *fmstate;
2685 2161 : 64 : ModifyTable *plan = castNode(ModifyTable, mtstate->ps.plan);
2162 : 64 : EState *estate = mtstate->ps.state;
2163 : : Index resultRelation;
2710 2164 : 64 : Relation rel = resultRelInfo->ri_RelationDesc;
2165 : : RangeTblEntry *rte;
2166 : 64 : TupleDesc tupdesc = RelationGetDescr(rel);
2167 : : int attnum;
2168 : : int values_end_len;
2169 : : StringInfoData sql;
2170 : 64 : List *targetAttrs = NIL;
2171 : 64 : List *retrieved_attrs = NIL;
2172 : 64 : bool doNothing = false;
2173 : :
2174 : : /*
2175 : : * If the foreign table we are about to insert routed rows into is also an
2176 : : * UPDATE subplan result rel that will be updated later, proceeding with
2177 : : * the INSERT will result in the later UPDATE incorrectly modifying those
2178 : : * routed rows, so prevent the INSERT --- it would be nice if we could
2179 : : * handle this case; but for now, throw an error for safety.
2180 : : */
2327 efujita@postgresql.o 2181 [ + + + + ]: 64 : if (plan && plan->operation == CMD_UPDATE &&
2182 [ + + ]: 9 : (resultRelInfo->ri_usesFdwDirectModify ||
1620 tgl@sss.pgh.pa.us 2183 [ + + ]: 5 : resultRelInfo->ri_FdwState))
2327 efujita@postgresql.o 2184 [ + - ]: 6 : ereport(ERROR,
2185 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2186 : : errmsg("cannot route tuples into foreign table to be updated \"%s\"",
2187 : : RelationGetRelationName(rel))));
2188 : :
2710 rhaas@postgresql.org 2189 : 58 : initStringInfo(&sql);
2190 : :
2191 : : /* We transmit all columns that are defined in the foreign table. */
2192 [ + + ]: 173 : for (attnum = 1; attnum <= tupdesc->natts; attnum++)
2193 : : {
260 drowley@postgresql.o 2194 : 115 : CompactAttribute *attr = TupleDescCompactAttr(tupdesc, attnum - 1);
2195 : :
2710 rhaas@postgresql.org 2196 [ + + ]: 115 : if (!attr->attisdropped)
2197 : 113 : targetAttrs = lappend_int(targetAttrs, attnum);
2198 : : }
2199 : :
2200 : : /* Check if we add the ON CONFLICT clause to the remote query. */
2201 [ + + ]: 58 : if (plan)
2202 : : {
2684 2203 : 34 : OnConflictAction onConflictAction = plan->onConflictAction;
2204 : :
2205 : : /* We only support DO NOTHING without an inference specification. */
2710 2206 [ + + ]: 34 : if (onConflictAction == ONCONFLICT_NOTHING)
2207 : 2 : doNothing = true;
2208 [ - + ]: 32 : else if (onConflictAction != ONCONFLICT_NONE)
2710 rhaas@postgresql.org 2209 [ # # ]:UBC 0 : elog(ERROR, "unexpected ON CONFLICT specification: %d",
2210 : : (int) onConflictAction);
2211 : : }
2212 : :
2213 : : /*
2214 : : * If the foreign table is a partition that doesn't have a corresponding
2215 : : * RTE entry, we need to create a new RTE describing the foreign table for
2216 : : * use by deparseInsertSql and create_foreign_modify() below, after first
2217 : : * copying the parent's RTE and modifying some fields to describe the
2218 : : * foreign partition to work on. However, if this is invoked by UPDATE,
2219 : : * the existing RTE may already correspond to this partition if it is one
2220 : : * of the UPDATE subplan target rels; in that case, we can just use the
2221 : : * existing RTE as-is.
2222 : : */
1671 heikki.linnakangas@i 2223 [ + + ]:CBC 58 : if (resultRelInfo->ri_RangeTableIndex == 0)
2224 : : {
2225 : 40 : ResultRelInfo *rootResultRelInfo = resultRelInfo->ri_RootResultRelInfo;
2226 : :
2227 : 40 : rte = exec_rt_fetch(rootResultRelInfo->ri_RangeTableIndex, estate);
2685 rhaas@postgresql.org 2228 : 40 : rte = copyObject(rte);
2229 : 40 : rte->relid = RelationGetRelid(rel);
2230 : 40 : rte->relkind = RELKIND_FOREIGN_TABLE;
2231 : :
2232 : : /*
2233 : : * For UPDATE, we must use the RT index of the first subplan target
2234 : : * rel's RTE, because the core code would have built expressions for
2235 : : * the partition, such as RETURNING, using that RT index as varno of
2236 : : * Vars contained in those expressions.
2237 : : */
2238 [ + + + + ]: 40 : if (plan && plan->operation == CMD_UPDATE &&
1671 heikki.linnakangas@i 2239 [ + - ]: 3 : rootResultRelInfo->ri_RangeTableIndex == plan->rootRelation)
2685 rhaas@postgresql.org 2240 : 3 : resultRelation = mtstate->resultRelInfo[0].ri_RangeTableIndex;
2241 : : else
1671 heikki.linnakangas@i 2242 : 37 : resultRelation = rootResultRelInfo->ri_RangeTableIndex;
2243 : : }
2244 : : else
2245 : : {
2246 : 18 : resultRelation = resultRelInfo->ri_RangeTableIndex;
2247 : 18 : rte = exec_rt_fetch(resultRelation, estate);
2248 : : }
2249 : :
2250 : : /* Construct the SQL command string. */
2685 rhaas@postgresql.org 2251 : 58 : deparseInsertSql(&sql, rte, resultRelation, rel, targetAttrs, doNothing,
2252 : : resultRelInfo->ri_WithCheckOptions,
2253 : : resultRelInfo->ri_returningList,
2254 : : &retrieved_attrs, &values_end_len);
2255 : :
2256 : : /* Construct an execution state. */
2710 2257 : 58 : fmstate = create_foreign_modify(mtstate->ps.state,
2258 : : rte,
2259 : : resultRelInfo,
2260 : : CMD_INSERT,
2261 : : NULL,
2262 : : sql.data,
2263 : : targetAttrs,
2264 : : values_end_len,
2265 : : retrieved_attrs != NIL,
2266 : : retrieved_attrs);
2267 : :
2268 : : /*
2269 : : * If the given resultRelInfo already has PgFdwModifyState set, it means
2270 : : * the foreign table is an UPDATE subplan result rel; in which case, store
2271 : : * the resulting state into the aux_fmstate of the PgFdwModifyState.
2272 : : */
2327 efujita@postgresql.o 2273 [ - + ]: 58 : if (resultRelInfo->ri_FdwState)
2274 : : {
2327 efujita@postgresql.o 2275 [ # # # # ]:UBC 0 : Assert(plan && plan->operation == CMD_UPDATE);
2276 [ # # ]: 0 : Assert(resultRelInfo->ri_usesFdwDirectModify == false);
2277 : 0 : ((PgFdwModifyState *) resultRelInfo->ri_FdwState)->aux_fmstate = fmstate;
2278 : : }
2279 : : else
2327 efujita@postgresql.o 2280 :CBC 58 : resultRelInfo->ri_FdwState = fmstate;
2710 rhaas@postgresql.org 2281 : 58 : }
2282 : :
2283 : : /*
2284 : : * postgresEndForeignInsert
2285 : : * Finish an insert operation on a foreign table
2286 : : */
2287 : : static void
2288 : 50 : postgresEndForeignInsert(EState *estate,
2289 : : ResultRelInfo *resultRelInfo)
2290 : : {
2291 : 50 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
2292 : :
2293 [ - + ]: 50 : Assert(fmstate != NULL);
2294 : :
2295 : : /*
2296 : : * If the fmstate has aux_fmstate set, get the aux_fmstate (see
2297 : : * postgresBeginForeignInsert())
2298 : : */
2327 efujita@postgresql.o 2299 [ - + ]: 50 : if (fmstate->aux_fmstate)
2327 efujita@postgresql.o 2300 :UBC 0 : fmstate = fmstate->aux_fmstate;
2301 : :
2302 : : /* Destroy the execution state */
2710 rhaas@postgresql.org 2303 :CBC 50 : finish_foreign_modify(fmstate);
2304 : 50 : }
2305 : :
2306 : : /*
2307 : : * postgresIsForeignRelUpdatable
2308 : : * Determine whether a foreign table supports INSERT, UPDATE and/or
2309 : : * DELETE.
2310 : : */
2311 : : static int
4469 tgl@sss.pgh.pa.us 2312 : 338 : postgresIsForeignRelUpdatable(Relation rel)
2313 : : {
2314 : : bool updatable;
2315 : : ForeignTable *table;
2316 : : ForeignServer *server;
2317 : : ListCell *lc;
2318 : :
2319 : : /*
2320 : : * By default, all postgres_fdw foreign tables are assumed updatable. This
2321 : : * can be overridden by a per-server setting, which in turn can be
2322 : : * overridden by a per-table setting.
2323 : : */
2324 : 338 : updatable = true;
2325 : :
2326 : 338 : table = GetForeignTable(RelationGetRelid(rel));
2327 : 338 : server = GetForeignServer(table->serverid);
2328 : :
2329 [ + - + + : 1511 : foreach(lc, server->options)
+ + ]
2330 : : {
2331 : 1173 : DefElem *def = (DefElem *) lfirst(lc);
2332 : :
2333 [ - + ]: 1173 : if (strcmp(def->defname, "updatable") == 0)
4469 tgl@sss.pgh.pa.us 2334 :UBC 0 : updatable = defGetBoolean(def);
2335 : : }
4469 tgl@sss.pgh.pa.us 2336 [ + - + + :CBC 814 : foreach(lc, table->options)
+ + ]
2337 : : {
2338 : 476 : DefElem *def = (DefElem *) lfirst(lc);
2339 : :
2340 [ - + ]: 476 : if (strcmp(def->defname, "updatable") == 0)
4469 tgl@sss.pgh.pa.us 2341 :UBC 0 : updatable = defGetBoolean(def);
2342 : : }
2343 : :
2344 : : /*
2345 : : * Currently "updatable" means support for INSERT, UPDATE and DELETE.
2346 : : */
2347 : : return updatable ?
4469 tgl@sss.pgh.pa.us 2348 [ + - ]:CBC 338 : (1 << CMD_INSERT) | (1 << CMD_UPDATE) | (1 << CMD_DELETE) : 0;
2349 : : }
2350 : :
2351 : : /*
2352 : : * postgresRecheckForeignScan
2353 : : * Execute a local join execution plan for a foreign join
2354 : : */
2355 : : static bool
3497 rhaas@postgresql.org 2356 :UBC 0 : postgresRecheckForeignScan(ForeignScanState *node, TupleTableSlot *slot)
2357 : : {
2358 : 0 : Index scanrelid = ((Scan *) node->ss.ps.plan)->scanrelid;
2359 : 0 : PlanState *outerPlan = outerPlanState(node);
2360 : : TupleTableSlot *result;
2361 : :
2362 : : /* For base foreign relations, it suffices to set fdw_recheck_quals */
2363 [ # # ]: 0 : if (scanrelid > 0)
2364 : 0 : return true;
2365 : :
2366 [ # # ]: 0 : Assert(outerPlan != NULL);
2367 : :
2368 : : /* Execute a local join execution plan */
2369 : 0 : result = ExecProcNode(outerPlan);
2370 [ # # # # ]: 0 : if (TupIsNull(result))
2371 : 0 : return false;
2372 : :
2373 : : /* Store result in the given slot */
2374 : 0 : ExecCopySlot(slot, result);
2375 : :
2376 : 0 : return true;
2377 : : }
2378 : :
2379 : : /*
2380 : : * find_modifytable_subplan
2381 : : * Helper routine for postgresPlanDirectModify to find the
2382 : : * ModifyTable subplan node that scans the specified RTI.
2383 : : *
2384 : : * Returns NULL if the subplan couldn't be identified. That's not a fatal
2385 : : * error condition, we just abandon trying to do the update directly.
2386 : : */
2387 : : static ForeignScan *
1620 tgl@sss.pgh.pa.us 2388 :CBC 131 : find_modifytable_subplan(PlannerInfo *root,
2389 : : ModifyTable *plan,
2390 : : Index rtindex,
2391 : : int subplan_index)
2392 : : {
2393 : 131 : Plan *subplan = outerPlan(plan);
2394 : :
2395 : : /*
2396 : : * The cases we support are (1) the desired ForeignScan is the immediate
2397 : : * child of ModifyTable, or (2) it is the subplan_index'th child of an
2398 : : * Append node that is the immediate child of ModifyTable. There is no
2399 : : * point in looking further down, as that would mean that local joins are
2400 : : * involved, so we can't do the update directly.
2401 : : *
2402 : : * There could be a Result atop the Append too, acting to compute the
2403 : : * UPDATE targetlist values. We ignore that here; the tlist will be
2404 : : * checked by our caller.
2405 : : *
2406 : : * In principle we could examine all the children of the Append, but it's
2407 : : * currently unlikely that the core planner would generate such a plan
2408 : : * with the children out-of-order. Moreover, such a search risks costing
2409 : : * O(N^2) time when there are a lot of children.
2410 : : */
2411 [ + + ]: 131 : if (IsA(subplan, Append))
2412 : : {
2413 : 33 : Append *appendplan = (Append *) subplan;
2414 : :
2415 [ + - ]: 33 : if (subplan_index < list_length(appendplan->appendplans))
2416 : 33 : subplan = (Plan *) list_nth(appendplan->appendplans, subplan_index);
2417 : : }
1522 2418 [ + + ]: 98 : else if (IsA(subplan, Result) &&
2419 [ + + ]: 6 : outerPlan(subplan) != NULL &&
2420 [ + - ]: 5 : IsA(outerPlan(subplan), Append))
2421 : : {
1620 2422 : 5 : Append *appendplan = (Append *) outerPlan(subplan);
2423 : :
2424 [ + - ]: 5 : if (subplan_index < list_length(appendplan->appendplans))
2425 : 5 : subplan = (Plan *) list_nth(appendplan->appendplans, subplan_index);
2426 : : }
2427 : :
2428 : : /* Now, have we got a ForeignScan on the desired rel? */
2429 [ + + ]: 131 : if (IsA(subplan, ForeignScan))
2430 : : {
2431 : 114 : ForeignScan *fscan = (ForeignScan *) subplan;
2432 : :
950 2433 [ + - ]: 114 : if (bms_is_member(rtindex, fscan->fs_base_relids))
1620 2434 : 114 : return fscan;
2435 : : }
2436 : :
2437 : 17 : return NULL;
2438 : : }
2439 : :
2440 : : /*
2441 : : * postgresPlanDirectModify
2442 : : * Consider a direct foreign table modification
2443 : : *
2444 : : * Decide whether it is safe to modify a foreign table directly, and if so,
2445 : : * rewrite subplan accordingly.
2446 : : */
2447 : : static bool
3459 rhaas@postgresql.org 2448 : 195 : postgresPlanDirectModify(PlannerInfo *root,
2449 : : ModifyTable *plan,
2450 : : Index resultRelation,
2451 : : int subplan_index)
2452 : : {
2453 : 195 : CmdType operation = plan->operation;
2454 : : RelOptInfo *foreignrel;
2455 : : RangeTblEntry *rte;
2456 : : PgFdwRelationInfo *fpinfo;
2457 : : Relation rel;
2458 : : StringInfoData sql;
2459 : : ForeignScan *fscan;
1620 tgl@sss.pgh.pa.us 2460 : 195 : List *processed_tlist = NIL;
3459 rhaas@postgresql.org 2461 : 195 : List *targetAttrs = NIL;
2462 : : List *remote_exprs;
2463 : 195 : List *params_list = NIL;
2464 : 195 : List *returningList = NIL;
2465 : 195 : List *retrieved_attrs = NIL;
2466 : :
2467 : : /*
2468 : : * Decide whether it is safe to modify a foreign table directly.
2469 : : */
2470 : :
2471 : : /*
2472 : : * The table modification must be an UPDATE or DELETE.
2473 : : */
2474 [ + + + + ]: 195 : if (operation != CMD_UPDATE && operation != CMD_DELETE)
2475 : 64 : return false;
2476 : :
2477 : : /*
2478 : : * Try to locate the ForeignScan subplan that's scanning resultRelation.
2479 : : */
1620 tgl@sss.pgh.pa.us 2480 : 131 : fscan = find_modifytable_subplan(root, plan, resultRelation, subplan_index);
2481 [ + + ]: 131 : if (!fscan)
3459 rhaas@postgresql.org 2482 : 17 : return false;
2483 : :
2484 : : /*
2485 : : * It's unsafe to modify a foreign table directly if there are any quals
2486 : : * that should be evaluated locally.
2487 : : */
1620 tgl@sss.pgh.pa.us 2488 [ + + ]: 114 : if (fscan->scan.plan.qual != NIL)
3459 rhaas@postgresql.org 2489 : 5 : return false;
2490 : :
2491 : : /* Safe to fetch data about the target foreign rel */
2768 2492 [ + + ]: 109 : if (fscan->scan.scanrelid == 0)
2493 : : {
2494 : 10 : foreignrel = find_join_rel(root, fscan->fs_relids);
2495 : : /* We should have a rel for this foreign join. */
2496 [ - + ]: 10 : Assert(foreignrel);
2497 : : }
2498 : : else
2499 : 99 : foreignrel = root->simple_rel_array[resultRelation];
3070 tgl@sss.pgh.pa.us 2500 : 109 : rte = root->simple_rte_array[resultRelation];
2501 : 109 : fpinfo = (PgFdwRelationInfo *) foreignrel->fdw_private;
2502 : :
2503 : : /*
2504 : : * It's unsafe to update a foreign table directly, if any expressions to
2505 : : * assign to the target columns are unsafe to evaluate remotely.
2506 : : */
3459 rhaas@postgresql.org 2507 [ + + ]: 109 : if (operation == CMD_UPDATE)
2508 : : {
2509 : : ListCell *lc,
2510 : : *lc2;
2511 : :
2512 : : /*
2513 : : * The expressions of concern are the first N columns of the processed
2514 : : * targetlist, where N is the length of the rel's update_colnos.
2515 : : */
1620 tgl@sss.pgh.pa.us 2516 : 50 : get_translated_update_targetlist(root, resultRelation,
2517 : : &processed_tlist, &targetAttrs);
2518 [ + - + - : 103 : forboth(lc, processed_tlist, lc2, targetAttrs)
+ - + + +
- + + +
+ ]
2519 : : {
2520 : 58 : TargetEntry *tle = lfirst_node(TargetEntry, lc);
2521 : 58 : AttrNumber attno = lfirst_int(lc2);
2522 : :
2523 : : /* update's new-value expressions shouldn't be resjunk */
2524 [ - + ]: 58 : Assert(!tle->resjunk);
2525 : :
2999 2526 [ - + ]: 58 : if (attno <= InvalidAttrNumber) /* shouldn't happen */
3459 rhaas@postgresql.org 2527 [ # # ]:UBC 0 : elog(ERROR, "system-column update is not supported");
2528 : :
3070 tgl@sss.pgh.pa.us 2529 [ + + ]:CBC 58 : if (!is_foreign_expr(root, foreignrel, (Expr *) tle->expr))
3459 rhaas@postgresql.org 2530 : 5 : return false;
2531 : : }
2532 : : }
2533 : :
2534 : : /*
2535 : : * Ok, rewrite subplan so as to modify the foreign table directly.
2536 : : */
2537 : 104 : initStringInfo(&sql);
2538 : :
2539 : : /*
2540 : : * Core code already has some lock on each rel being planned, so we can
2541 : : * use NoLock here.
2542 : : */
2420 andres@anarazel.de 2543 : 104 : rel = table_open(rte->relid, NoLock);
2544 : :
2545 : : /*
2546 : : * Recall the qual clauses that must be evaluated remotely. (These are
2547 : : * bare clauses not RestrictInfos, but deparse.c's appendConditions()
2548 : : * doesn't care.)
2549 : : */
3070 tgl@sss.pgh.pa.us 2550 : 104 : remote_exprs = fpinfo->final_remote_exprs;
2551 : :
2552 : : /*
2553 : : * Extract the relevant RETURNING list if any.
2554 : : */
3459 rhaas@postgresql.org 2555 [ + + ]: 104 : if (plan->returningLists)
2556 : : {
2557 : 35 : returningList = (List *) list_nth(plan->returningLists, subplan_index);
2558 : :
2559 : : /*
2560 : : * When performing an UPDATE/DELETE .. RETURNING on a join directly,
2561 : : * we fetch from the foreign server any Vars specified in RETURNING
2562 : : * that refer not only to the target relation but to non-target
2563 : : * relations. So we'll deparse them into the RETURNING clause of the
2564 : : * remote query; use a targetlist consisting of them instead, which
2565 : : * will be adjusted to be new fdw_scan_tlist of the foreign-scan plan
2566 : : * node below.
2567 : : */
2768 2568 [ + + ]: 35 : if (fscan->scan.scanrelid == 0)
2569 : 4 : returningList = build_remote_returning(resultRelation, rel,
2570 : : returningList);
2571 : : }
2572 : :
2573 : : /*
2574 : : * Construct the SQL command string.
2575 : : */
3459 2576 [ + + - ]: 104 : switch (operation)
2577 : : {
2578 : 45 : case CMD_UPDATE:
2579 : 45 : deparseDirectUpdateSql(&sql, root, resultRelation, rel,
2580 : : foreignrel,
2581 : : processed_tlist,
2582 : : targetAttrs,
2583 : : remote_exprs, ¶ms_list,
2584 : : returningList, &retrieved_attrs);
2585 : 45 : break;
2586 : 59 : case CMD_DELETE:
2587 : 59 : deparseDirectDeleteSql(&sql, root, resultRelation, rel,
2588 : : foreignrel,
2589 : : remote_exprs, ¶ms_list,
2590 : : returningList, &retrieved_attrs);
2591 : 59 : break;
3459 rhaas@postgresql.org 2592 :UBC 0 : default:
2593 [ # # ]: 0 : elog(ERROR, "unexpected operation: %d", (int) operation);
2594 : : break;
2595 : : }
2596 : :
2597 : : /*
2598 : : * Update the operation and target relation info.
2599 : : */
3459 rhaas@postgresql.org 2600 :CBC 104 : fscan->operation = operation;
1788 heikki.linnakangas@i 2601 : 104 : fscan->resultRelation = resultRelation;
2602 : :
2603 : : /*
2604 : : * Update the fdw_exprs list that will be available to the executor.
2605 : : */
3459 rhaas@postgresql.org 2606 : 104 : fscan->fdw_exprs = params_list;
2607 : :
2608 : : /*
2609 : : * Update the fdw_private list that will be available to the executor.
2610 : : * Items in the list must match enum FdwDirectModifyPrivateIndex, above.
2611 : : */
2612 : 104 : fscan->fdw_private = list_make4(makeString(sql.data),
2613 : : makeBoolean((retrieved_attrs != NIL)),
2614 : : retrieved_attrs,
2615 : : makeBoolean(plan->canSetTag));
2616 : :
2617 : : /*
2618 : : * Update the foreign-join-related fields.
2619 : : */
2768 2620 [ + + ]: 104 : if (fscan->scan.scanrelid == 0)
2621 : : {
2622 : : /* No need for the outer subplan. */
2623 : 8 : fscan->scan.plan.lefttree = NULL;
2624 : :
2625 : : /* Build new fdw_scan_tlist if UPDATE/DELETE .. RETURNING. */
2626 [ + + ]: 8 : if (returningList)
2627 : 2 : rebuild_fdw_scan_tlist(fscan, returningList);
2628 : : }
2629 : :
2630 : : /*
2631 : : * Finally, unset the async-capable flag if it is set, as we currently
2632 : : * don't support asynchronous execution of direct modifications.
2633 : : */
1577 efujita@postgresql.o 2634 [ + + ]: 104 : if (fscan->scan.plan.async_capable)
2635 : 8 : fscan->scan.plan.async_capable = false;
2636 : :
2420 andres@anarazel.de 2637 : 104 : table_close(rel, NoLock);
3459 rhaas@postgresql.org 2638 : 104 : return true;
2639 : : }
2640 : :
2641 : : /*
2642 : : * postgresBeginDirectModify
2643 : : * Prepare a direct foreign table modification
2644 : : */
2645 : : static void
2646 : 104 : postgresBeginDirectModify(ForeignScanState *node, int eflags)
2647 : : {
2648 : 104 : ForeignScan *fsplan = (ForeignScan *) node->ss.ps.plan;
2649 : 104 : EState *estate = node->ss.ps.state;
2650 : : PgFdwDirectModifyState *dmstate;
2651 : : Index rtindex;
2652 : : Oid userid;
2653 : : ForeignTable *table;
2654 : : UserMapping *user;
2655 : : int numParams;
2656 : :
2657 : : /*
2658 : : * Do nothing in EXPLAIN (no ANALYZE) case. node->fdw_state stays NULL.
2659 : : */
2660 [ + + ]: 104 : if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
2661 : 32 : return;
2662 : :
2663 : : /*
2664 : : * We'll save private state in node->fdw_state.
2665 : : */
2666 : 72 : dmstate = (PgFdwDirectModifyState *) palloc0(sizeof(PgFdwDirectModifyState));
282 peter@eisentraut.org 2667 : 72 : node->fdw_state = dmstate;
2668 : :
2669 : : /*
2670 : : * Identify which user to do the remote access as. This should match what
2671 : : * ExecCheckPermissions() does.
2672 : : */
1011 alvherre@alvh.no-ip. 2673 [ - + ]: 72 : userid = OidIsValid(fsplan->checkAsUser) ? fsplan->checkAsUser : GetUserId();
2674 : :
2675 : : /* Get info about foreign table. */
2676 : 72 : rtindex = node->resultRelInfo->ri_RangeTableIndex;
2768 rhaas@postgresql.org 2677 [ + + ]: 72 : if (fsplan->scan.scanrelid == 0)
2678 : 4 : dmstate->rel = ExecOpenScanRelation(estate, rtindex, eflags);
2679 : : else
2680 : 68 : dmstate->rel = node->ss.ss_currentRelation;
3459 2681 : 72 : table = GetForeignTable(RelationGetRelid(dmstate->rel));
2682 : 72 : user = GetUserMapping(userid, table->serverid);
2683 : :
2684 : : /*
2685 : : * Get connection to the foreign server. Connection manager will
2686 : : * establish new connection if necessary.
2687 : : */
1620 efujita@postgresql.o 2688 : 72 : dmstate->conn = GetConnection(user, false, &dmstate->conn_state);
2689 : :
2690 : : /* Update the foreign-join-related fields. */
2768 rhaas@postgresql.org 2691 [ + + ]: 72 : if (fsplan->scan.scanrelid == 0)
2692 : : {
2693 : : /* Save info about foreign table. */
2694 : 4 : dmstate->resultRel = dmstate->rel;
2695 : :
2696 : : /*
2697 : : * Set dmstate->rel to NULL to teach get_returning_data() and
2698 : : * make_tuple_from_result_row() that columns fetched from the remote
2699 : : * server are described by fdw_scan_tlist of the foreign-scan plan
2700 : : * node, not the tuple descriptor for the target relation.
2701 : : */
2702 : 4 : dmstate->rel = NULL;
2703 : : }
2704 : :
2705 : : /* Initialize state variable */
3440 tgl@sss.pgh.pa.us 2706 : 72 : dmstate->num_tuples = -1; /* -1 means not set yet */
2707 : :
2708 : : /* Get private info created by planner functions. */
3459 rhaas@postgresql.org 2709 : 72 : dmstate->query = strVal(list_nth(fsplan->fdw_private,
2710 : : FdwDirectModifyPrivateUpdateSql));
1331 peter@eisentraut.org 2711 : 72 : dmstate->has_returning = boolVal(list_nth(fsplan->fdw_private,
2712 : : FdwDirectModifyPrivateHasReturning));
3459 rhaas@postgresql.org 2713 : 72 : dmstate->retrieved_attrs = (List *) list_nth(fsplan->fdw_private,
2714 : : FdwDirectModifyPrivateRetrievedAttrs);
1331 peter@eisentraut.org 2715 : 72 : dmstate->set_processed = boolVal(list_nth(fsplan->fdw_private,
2716 : : FdwDirectModifyPrivateSetProcessed));
2717 : :
2718 : : /* Create context for per-tuple temp workspace. */
3459 rhaas@postgresql.org 2719 : 72 : dmstate->temp_cxt = AllocSetContextCreate(estate->es_query_cxt,
2720 : : "postgres_fdw temporary data",
2721 : : ALLOCSET_SMALL_SIZES);
2722 : :
2723 : : /* Prepare for input conversion of RETURNING results. */
2724 [ + + ]: 72 : if (dmstate->has_returning)
2725 : : {
2726 : : TupleDesc tupdesc;
2727 : :
2768 2728 [ + + ]: 16 : if (fsplan->scan.scanrelid == 0)
1555 tgl@sss.pgh.pa.us 2729 : 1 : tupdesc = get_tupdesc_for_join_scan_tuples(node);
2730 : : else
2768 rhaas@postgresql.org 2731 : 15 : tupdesc = RelationGetDescr(dmstate->rel);
2732 : :
2733 : 16 : dmstate->attinmeta = TupleDescGetAttInMetadata(tupdesc);
2734 : :
2735 : : /*
2736 : : * When performing an UPDATE/DELETE .. RETURNING on a join directly,
2737 : : * initialize a filter to extract an updated/deleted tuple from a scan
2738 : : * tuple.
2739 : : */
2740 [ + + ]: 16 : if (fsplan->scan.scanrelid == 0)
2741 : 1 : init_returning_filter(dmstate, fsplan->fdw_scan_tlist, rtindex);
2742 : : }
2743 : :
2744 : : /*
2745 : : * Prepare for processing of parameters used in remote query, if any.
2746 : : */
3459 2747 : 72 : numParams = list_length(fsplan->fdw_exprs);
2748 : 72 : dmstate->numParams = numParams;
2749 [ - + ]: 72 : if (numParams > 0)
3459 rhaas@postgresql.org 2750 :UBC 0 : prepare_query_params((PlanState *) node,
2751 : : fsplan->fdw_exprs,
2752 : : numParams,
2753 : : &dmstate->param_flinfo,
2754 : : &dmstate->param_exprs,
2755 : : &dmstate->param_values);
2756 : : }
2757 : :
2758 : : /*
2759 : : * postgresIterateDirectModify
2760 : : * Execute a direct foreign table modification
2761 : : */
2762 : : static TupleTableSlot *
3459 rhaas@postgresql.org 2763 :CBC 418 : postgresIterateDirectModify(ForeignScanState *node)
2764 : : {
2765 : 418 : PgFdwDirectModifyState *dmstate = (PgFdwDirectModifyState *) node->fdw_state;
2766 : 418 : EState *estate = node->ss.ps.state;
1788 heikki.linnakangas@i 2767 : 418 : ResultRelInfo *resultRelInfo = node->resultRelInfo;
2768 : :
2769 : : /*
2770 : : * If this is the first call after Begin, execute the statement.
2771 : : */
3459 rhaas@postgresql.org 2772 [ + + ]: 418 : if (dmstate->num_tuples == -1)
2773 : 71 : execute_dml_stmt(node);
2774 : :
2775 : : /*
2776 : : * If the local query doesn't specify RETURNING, just clear tuple slot.
2777 : : */
2778 [ + + ]: 414 : if (!resultRelInfo->ri_projectReturning)
2779 : : {
2780 : 50 : TupleTableSlot *slot = node->ss.ss_ScanTupleSlot;
2781 : 50 : Instrumentation *instr = node->ss.ps.instrument;
2782 : :
2783 [ - + ]: 50 : Assert(!dmstate->has_returning);
2784 : :
2785 : : /* Increment the command es_processed count if necessary. */
2786 [ + - ]: 50 : if (dmstate->set_processed)
2787 : 50 : estate->es_processed += dmstate->num_tuples;
2788 : :
2789 : : /* Increment the tuple count for EXPLAIN ANALYZE if necessary. */
2790 [ - + ]: 50 : if (instr)
3459 rhaas@postgresql.org 2791 :UBC 0 : instr->tuplecount += dmstate->num_tuples;
2792 : :
3459 rhaas@postgresql.org 2793 :CBC 50 : return ExecClearTuple(slot);
2794 : : }
2795 : :
2796 : : /*
2797 : : * Get the next RETURNING tuple.
2798 : : */
2799 : 364 : return get_returning_data(node);
2800 : : }
2801 : :
2802 : : /*
2803 : : * postgresEndDirectModify
2804 : : * Finish a direct foreign table modification
2805 : : */
2806 : : static void
2807 : 96 : postgresEndDirectModify(ForeignScanState *node)
2808 : : {
2809 : 96 : PgFdwDirectModifyState *dmstate = (PgFdwDirectModifyState *) node->fdw_state;
2810 : :
2811 : : /* if dmstate is NULL, we are in EXPLAIN; nothing to do */
2812 [ + + ]: 96 : if (dmstate == NULL)
2813 : 32 : return;
2814 : :
2815 : : /* Release PGresult */
43 tgl@sss.pgh.pa.us 2816 :GNC 64 : PQclear(dmstate->result);
2817 : :
2818 : : /* Release remote connection */
3459 rhaas@postgresql.org 2819 :CBC 64 : ReleaseConnection(dmstate->conn);
2820 : 64 : dmstate->conn = NULL;
2821 : :
2822 : : /* MemoryContext will be deleted automatically. */
2823 : : }
2824 : :
2825 : : /*
2826 : : * postgresExplainForeignScan
2827 : : * Produce extra output for EXPLAIN of a ForeignScan on a foreign table
2828 : : */
2829 : : static void
4563 tgl@sss.pgh.pa.us 2830 : 390 : postgresExplainForeignScan(ForeignScanState *node, ExplainState *es)
2831 : : {
2105 2832 : 390 : ForeignScan *plan = castNode(ForeignScan, node->ss.ps.plan);
2833 : 390 : List *fdw_private = plan->fdw_private;
2834 : :
2835 : : /*
2836 : : * Identify foreign scans that are really joins or upper relations. The
2837 : : * input looks something like "(1) LEFT JOIN (2)", and we must replace the
2838 : : * digit string(s), which are RT indexes, with the correct relation names.
2839 : : * We do that here, not when the plan is created, because we can't know
2840 : : * what aliases ruleutils.c will assign at plan creation time.
2841 : : */
3497 rhaas@postgresql.org 2842 [ + + ]: 390 : if (list_length(fdw_private) > FdwScanPrivateRelations)
2843 : : {
2844 : : StringInfo relations;
2845 : : char *rawrelations;
2846 : : char *ptr;
2847 : : int minrti,
2848 : : rtoffset;
2849 : :
2105 tgl@sss.pgh.pa.us 2850 : 121 : rawrelations = strVal(list_nth(fdw_private, FdwScanPrivateRelations));
2851 : :
2852 : : /*
2853 : : * A difficulty with using a string representation of RT indexes is
2854 : : * that setrefs.c won't update the string when flattening the
2855 : : * rangetable. To find out what rtoffset was applied, identify the
2856 : : * minimum RT index appearing in the string and compare it to the
2857 : : * minimum member of plan->fs_base_relids. (We expect all the relids
2858 : : * in the join will have been offset by the same amount; the Asserts
2859 : : * below should catch it if that ever changes.)
2860 : : */
2861 : 121 : minrti = INT_MAX;
2862 : 121 : ptr = rawrelations;
2863 [ + + ]: 2877 : while (*ptr)
2864 : : {
2865 [ + + ]: 2756 : if (isdigit((unsigned char) *ptr))
2866 : : {
2867 : 239 : int rti = strtol(ptr, &ptr, 10);
2868 : :
2869 [ + + ]: 239 : if (rti < minrti)
2870 : 133 : minrti = rti;
2871 : : }
2872 : : else
2873 : 2517 : ptr++;
2874 : : }
950 2875 : 121 : rtoffset = bms_next_member(plan->fs_base_relids, -1) - minrti;
2876 : :
2877 : : /* Now we can translate the string */
2105 2878 : 121 : relations = makeStringInfo();
2879 : 121 : ptr = rawrelations;
2880 [ + + ]: 2877 : while (*ptr)
2881 : : {
2882 [ + + ]: 2756 : if (isdigit((unsigned char) *ptr))
2883 : : {
2884 : 239 : int rti = strtol(ptr, &ptr, 10);
2885 : : RangeTblEntry *rte;
2886 : : char *relname;
2887 : : char *refname;
2888 : :
2889 : 239 : rti += rtoffset;
950 2890 [ - + ]: 239 : Assert(bms_is_member(rti, plan->fs_base_relids));
2105 2891 : 239 : rte = rt_fetch(rti, es->rtable);
2892 [ - + ]: 239 : Assert(rte->rtekind == RTE_RELATION);
2893 : : /* This logic should agree with explain.c's ExplainTargetRel */
2894 : 239 : relname = get_rel_name(rte->relid);
2104 2895 [ + + ]: 239 : if (es->verbose)
2896 : : {
2897 : : char *namespace;
2898 : :
1502 2899 : 226 : namespace = get_namespace_name_or_temp(get_rel_namespace(rte->relid));
2104 2900 : 226 : appendStringInfo(relations, "%s.%s",
2901 : : quote_identifier(namespace),
2902 : : quote_identifier(relname));
2903 : : }
2904 : : else
1787 drowley@postgresql.o 2905 : 13 : appendStringInfoString(relations,
2906 : : quote_identifier(relname));
2105 tgl@sss.pgh.pa.us 2907 : 239 : refname = (char *) list_nth(es->rtable_names, rti - 1);
2908 [ - + ]: 239 : if (refname == NULL)
2105 tgl@sss.pgh.pa.us 2909 :UBC 0 : refname = rte->eref->aliasname;
2105 tgl@sss.pgh.pa.us 2910 [ + + ]:CBC 239 : if (strcmp(refname, relname) != 0)
2911 : 149 : appendStringInfo(relations, " %s",
2912 : : quote_identifier(refname));
2913 : : }
2914 : : else
2915 : 2517 : appendStringInfoChar(relations, *ptr++);
2916 : : }
2917 : 121 : ExplainPropertyText("Relations", relations->data, es);
2918 : : }
2919 : :
2920 : : /*
2921 : : * Add remote query, when VERBOSE option is specified.
2922 : : */
4563 2923 [ + + ]: 390 : if (es->verbose)
2924 : : {
2925 : : char *sql;
2926 : :
2927 : 354 : sql = strVal(list_nth(fdw_private, FdwScanPrivateSelectSql));
2928 : 354 : ExplainPropertyText("Remote SQL", sql, es);
2929 : : }
2930 : 390 : }
2931 : :
2932 : : /*
2933 : : * postgresExplainForeignModify
2934 : : * Produce extra output for EXPLAIN of a ModifyTable on a foreign table
2935 : : */
2936 : : static void
2937 : 46 : postgresExplainForeignModify(ModifyTableState *mtstate,
2938 : : ResultRelInfo *rinfo,
2939 : : List *fdw_private,
2940 : : int subplan_index,
2941 : : ExplainState *es)
2942 : : {
2943 [ + - ]: 46 : if (es->verbose)
2944 : : {
2945 : 46 : char *sql = strVal(list_nth(fdw_private,
2946 : : FdwModifyPrivateUpdateSql));
2947 : :
2948 : 46 : ExplainPropertyText("Remote SQL", sql, es);
2949 : :
2950 : : /*
2951 : : * For INSERT we should always have batch size >= 1, but UPDATE and
2952 : : * DELETE don't support batching so don't show the property.
2953 : : */
1690 tomas.vondra@postgre 2954 [ + + ]: 46 : if (rinfo->ri_BatchSize > 0)
2955 : 13 : ExplainPropertyInteger("Batch Size", NULL, rinfo->ri_BatchSize, es);
2956 : : }
4563 tgl@sss.pgh.pa.us 2957 : 46 : }
2958 : :
2959 : : /*
2960 : : * postgresExplainDirectModify
2961 : : * Produce extra output for EXPLAIN of a ForeignScan that modifies a
2962 : : * foreign table directly
2963 : : */
2964 : : static void
3459 rhaas@postgresql.org 2965 : 32 : postgresExplainDirectModify(ForeignScanState *node, ExplainState *es)
2966 : : {
2967 : : List *fdw_private;
2968 : : char *sql;
2969 : :
2970 [ + - ]: 32 : if (es->verbose)
2971 : : {
2972 : 32 : fdw_private = ((ForeignScan *) node->ss.ps.plan)->fdw_private;
2973 : 32 : sql = strVal(list_nth(fdw_private, FdwDirectModifyPrivateUpdateSql));
2974 : 32 : ExplainPropertyText("Remote SQL", sql, es);
2975 : : }
2976 : 32 : }
2977 : :
2978 : : /*
2979 : : * postgresExecForeignTruncate
2980 : : * Truncate one or more foreign tables
2981 : : */
2982 : : static void
1612 fujii@postgresql.org 2983 : 15 : postgresExecForeignTruncate(List *rels,
2984 : : DropBehavior behavior,
2985 : : bool restart_seqs)
2986 : : {
2987 : 15 : Oid serverid = InvalidOid;
2988 : 15 : UserMapping *user = NULL;
2989 : 15 : PGconn *conn = NULL;
2990 : : StringInfoData sql;
2991 : : ListCell *lc;
2992 : 15 : bool server_truncatable = true;
2993 : :
2994 : : /*
2995 : : * By default, all postgres_fdw foreign tables are assumed truncatable.
2996 : : * This can be overridden by a per-server setting, which in turn can be
2997 : : * overridden by a per-table setting.
2998 : : */
2999 [ + - + + : 29 : foreach(lc, rels)
+ + ]
3000 : : {
3001 : 17 : ForeignServer *server = NULL;
3002 : 17 : Relation rel = lfirst(lc);
3003 : 17 : ForeignTable *table = GetForeignTable(RelationGetRelid(rel));
3004 : : ListCell *cell;
3005 : : bool truncatable;
3006 : :
3007 : : /*
3008 : : * First time through, determine whether the foreign server allows
3009 : : * truncates. Since all specified foreign tables are assumed to belong
3010 : : * to the same foreign server, this result can be used for other
3011 : : * foreign tables.
3012 : : */
3013 [ + + ]: 17 : if (!OidIsValid(serverid))
3014 : : {
3015 : 15 : serverid = table->serverid;
3016 : 15 : server = GetForeignServer(serverid);
3017 : :
3018 [ + - + + : 60 : foreach(cell, server->options)
+ + ]
3019 : : {
3020 : 48 : DefElem *defel = (DefElem *) lfirst(cell);
3021 : :
3022 [ + + ]: 48 : if (strcmp(defel->defname, "truncatable") == 0)
3023 : : {
3024 : 3 : server_truncatable = defGetBoolean(defel);
3025 : 3 : break;
3026 : : }
3027 : : }
3028 : : }
3029 : :
3030 : : /*
3031 : : * Confirm that all specified foreign tables belong to the same
3032 : : * foreign server.
3033 : : */
3034 [ - + ]: 17 : Assert(table->serverid == serverid);
3035 : :
3036 : : /* Determine whether this foreign table allows truncations */
3037 : 17 : truncatable = server_truncatable;
3038 [ + - + + : 34 : foreach(cell, table->options)
+ + ]
3039 : : {
3040 : 24 : DefElem *defel = (DefElem *) lfirst(cell);
3041 : :
3042 [ + + ]: 24 : if (strcmp(defel->defname, "truncatable") == 0)
3043 : : {
3044 : 7 : truncatable = defGetBoolean(defel);
3045 : 7 : break;
3046 : : }
3047 : : }
3048 : :
3049 [ + + ]: 17 : if (!truncatable)
3050 [ + - ]: 3 : ereport(ERROR,
3051 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3052 : : errmsg("foreign table \"%s\" does not allow truncates",
3053 : : RelationGetRelationName(rel))));
3054 : : }
3055 [ - + ]: 12 : Assert(OidIsValid(serverid));
3056 : :
3057 : : /*
3058 : : * Get connection to the foreign server. Connection manager will
3059 : : * establish new connection if necessary.
3060 : : */
3061 : 12 : user = GetUserMapping(GetUserId(), serverid);
3062 : 12 : conn = GetConnection(user, false, NULL);
3063 : :
3064 : : /* Construct the TRUNCATE command string */
3065 : 12 : initStringInfo(&sql);
1593 3066 : 12 : deparseTruncateSql(&sql, rels, behavior, restart_seqs);
3067 : :
3068 : : /* Issue the TRUNCATE command to remote server */
1612 3069 : 12 : do_sql_command(conn, sql.data);
3070 : :
3071 : 11 : pfree(sql.data);
3072 : 11 : }
3073 : :
3074 : : /*
3075 : : * estimate_path_cost_size
3076 : : * Get cost and size estimates for a foreign scan on given foreign relation
3077 : : * either a base relation or a join between foreign relations or an upper
3078 : : * relation containing foreign relations.
3079 : : *
3080 : : * param_join_conds are the parameterization clauses with outer relations.
3081 : : * pathkeys specify the expected sort order if any for given path being costed.
3082 : : * fpextra specifies additional post-scan/join-processing steps such as the
3083 : : * final sort and the LIMIT restriction.
3084 : : *
3085 : : * The function returns the cost and size estimates in p_rows, p_width,
3086 : : * p_disabled_nodes, p_startup_cost and p_total_cost variables.
3087 : : */
3088 : : static void
4552 tgl@sss.pgh.pa.us 3089 : 2686 : estimate_path_cost_size(PlannerInfo *root,
3090 : : RelOptInfo *foreignrel,
3091 : : List *param_join_conds,
3092 : : List *pathkeys,
3093 : : PgFdwPathExtraData *fpextra,
3094 : : double *p_rows, int *p_width,
3095 : : int *p_disabled_nodes,
3096 : : Cost *p_startup_cost, Cost *p_total_cost)
3097 : : {
3497 rhaas@postgresql.org 3098 : 2686 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) foreignrel->fdw_private;
3099 : : double rows;
3100 : : double retrieved_rows;
3101 : : int width;
381 3102 : 2686 : int disabled_nodes = 0;
3103 : : Cost startup_cost;
3104 : : Cost total_cost;
3105 : :
3106 : : /* Make sure the core code has set up the relation's reltarget */
2417 efujita@postgresql.o 3107 [ - + ]: 2686 : Assert(foreignrel->reltarget);
3108 : :
3109 : : /*
3110 : : * If the table or the server is configured to use remote estimates,
3111 : : * connect to the foreign server and execute EXPLAIN to estimate the
3112 : : * number of rows selected by the restriction+join clauses. Otherwise,
3113 : : * estimate rows using whatever statistics we have locally, in a way
3114 : : * similar to ordinary tables.
3115 : : */
4552 tgl@sss.pgh.pa.us 3116 [ + + ]: 2686 : if (fpinfo->use_remote_estimate)
3117 : : {
3118 : : List *remote_param_join_conds;
3119 : : List *local_param_join_conds;
3120 : : StringInfoData sql;
3121 : : PGconn *conn;
3122 : : Selectivity local_sel;
3123 : : QualCost local_cost;
3497 rhaas@postgresql.org 3124 : 1285 : List *fdw_scan_tlist = NIL;
3125 : : List *remote_conds;
3126 : :
3127 : : /* Required only to be passed to deparseSelectStmtForRel */
3128 : : List *retrieved_attrs;
3129 : :
3130 : : /*
3131 : : * param_join_conds might contain both clauses that are safe to send
3132 : : * across, and clauses that aren't.
3133 : : */
3134 : 1285 : classifyConditions(root, foreignrel, param_join_conds,
3135 : : &remote_param_join_conds, &local_param_join_conds);
3136 : :
3137 : : /* Build the list of columns to be fetched from the foreign server. */
3078 3138 [ + + + + : 1285 : if (IS_JOIN_REL(foreignrel) || IS_UPPER_REL(foreignrel))
+ + - + ]
3497 3139 : 521 : fdw_scan_tlist = build_tlist_to_deparse(foreignrel);
3140 : : else
3141 : 764 : fdw_scan_tlist = NIL;
3142 : :
3143 : : /*
3144 : : * The complete list of remote conditions includes everything from
3145 : : * baserestrictinfo plus any extra join_conds relevant to this
3146 : : * particular path.
3147 : : */
2217 tgl@sss.pgh.pa.us 3148 : 1285 : remote_conds = list_concat(remote_param_join_conds,
3507 rhaas@postgresql.org 3149 : 1285 : fpinfo->remote_conds);
3150 : :
3151 : : /*
3152 : : * Construct EXPLAIN query including the desired SELECT, FROM, and
3153 : : * WHERE clauses. Params and other-relation Vars are replaced by dummy
3154 : : * values, so don't request params_list.
3155 : : */
4552 tgl@sss.pgh.pa.us 3156 : 1285 : initStringInfo(&sql);
3157 : 1285 : appendStringInfoString(&sql, "EXPLAIN ");
3497 rhaas@postgresql.org 3158 : 1285 : deparseSelectStmtForRel(&sql, root, foreignrel, fdw_scan_tlist,
3159 : : remote_conds, pathkeys,
2349 efujita@postgresql.o 3160 [ + + + - ]: 1285 : fpextra ? fpextra->has_final_sort : false,
3161 [ + + + + ]: 1285 : fpextra ? fpextra->has_limit : false,
3162 : : false, &retrieved_attrs, NULL);
3163 : :
3164 : : /* Get the remote estimate */
1620 3165 : 1285 : conn = GetConnection(fpinfo->user, false, NULL);
4552 tgl@sss.pgh.pa.us 3166 : 1285 : get_remote_estimate(sql.data, conn, &rows, &width,
3167 : : &startup_cost, &total_cost);
3168 : 1285 : ReleaseConnection(conn);
3169 : :
3170 : 1285 : retrieved_rows = rows;
3171 : :
3172 : : /* Factor in the selectivity of the locally-checked quals */
4201 3173 : 1285 : local_sel = clauselist_selectivity(root,
3174 : : local_param_join_conds,
3497 rhaas@postgresql.org 3175 : 1285 : foreignrel->relid,
3176 : : JOIN_INNER,
3177 : : NULL);
4201 tgl@sss.pgh.pa.us 3178 : 1285 : local_sel *= fpinfo->local_conds_sel;
3179 : :
3180 : 1285 : rows = clamp_row_est(rows * local_sel);
3181 : :
3182 : : /* Add in the eval cost of the locally-checked quals */
4552 3183 : 1285 : startup_cost += fpinfo->local_conds_cost.startup;
3184 : 1285 : total_cost += fpinfo->local_conds_cost.per_tuple * retrieved_rows;
3497 rhaas@postgresql.org 3185 : 1285 : cost_qual_eval(&local_cost, local_param_join_conds, root);
4201 tgl@sss.pgh.pa.us 3186 : 1285 : startup_cost += local_cost.startup;
3187 : 1285 : total_cost += local_cost.per_tuple * retrieved_rows;
3188 : :
3189 : : /*
3190 : : * Add in tlist eval cost for each output row. In case of an
3191 : : * aggregate, some of the tlist expressions such as grouping
3192 : : * expressions will be evaluated remotely, so adjust the costs.
3193 : : */
2417 efujita@postgresql.o 3194 : 1285 : startup_cost += foreignrel->reltarget->cost.startup;
3195 : 1285 : total_cost += foreignrel->reltarget->cost.startup;
3196 : 1285 : total_cost += foreignrel->reltarget->cost.per_tuple * rows;
3197 [ + + - + ]: 1285 : if (IS_UPPER_REL(foreignrel))
3198 : : {
3199 : : QualCost tlist_cost;
3200 : :
3201 : 40 : cost_qual_eval(&tlist_cost, fdw_scan_tlist, root);
3202 : 40 : startup_cost -= tlist_cost.startup;
3203 : 40 : total_cost -= tlist_cost.startup;
3204 : 40 : total_cost -= tlist_cost.per_tuple * rows;
3205 : : }
3206 : : }
3207 : : else
3208 : : {
3497 rhaas@postgresql.org 3209 : 1401 : Cost run_cost = 0;
3210 : :
3211 : : /*
3212 : : * We don't support join conditions in this mode (hence, no
3213 : : * parameterized paths can be made).
3214 : : */
3215 [ - + ]: 1401 : Assert(param_join_conds == NIL);
3216 : :
3217 : : /*
3218 : : * We will come here again and again with different set of pathkeys or
3219 : : * additional post-scan/join-processing steps that caller wants to
3220 : : * cost. We don't need to calculate the cost/size estimates for the
3221 : : * underlying scan, join, or grouping each time. Instead, use those
3222 : : * estimates if we have cached them already.
3223 : : */
2412 efujita@postgresql.o 3224 [ + + + - ]: 1401 : if (fpinfo->rel_startup_cost >= 0 && fpinfo->rel_total_cost >= 0)
3225 : : {
1674 3226 [ - + ]: 310 : Assert(fpinfo->retrieved_rows >= 0);
3227 : :
2276 3228 : 310 : rows = fpinfo->rows;
3229 : 310 : retrieved_rows = fpinfo->retrieved_rows;
3230 : 310 : width = fpinfo->width;
3468 rhaas@postgresql.org 3231 : 310 : startup_cost = fpinfo->rel_startup_cost;
3232 : 310 : run_cost = fpinfo->rel_total_cost - fpinfo->rel_startup_cost;
3233 : :
3234 : : /*
3235 : : * If we estimate the costs of a foreign scan or a foreign join
3236 : : * with additional post-scan/join-processing steps, the scan or
3237 : : * join costs obtained from the cache wouldn't yet contain the
3238 : : * eval costs for the final scan/join target, which would've been
3239 : : * updated by apply_scanjoin_target_to_paths(); add the eval costs
3240 : : * now.
3241 : : */
2349 efujita@postgresql.o 3242 [ + + + + : 310 : if (fpextra && !IS_UPPER_REL(foreignrel))
+ - ]
3243 : : {
3244 : : /* Shouldn't get here unless we have LIMIT */
3245 [ - + ]: 90 : Assert(fpextra->has_limit);
3246 [ + + - + ]: 90 : Assert(foreignrel->reloptkind == RELOPT_BASEREL ||
3247 : : foreignrel->reloptkind == RELOPT_JOINREL);
3248 : 90 : startup_cost += foreignrel->reltarget->cost.startup;
3249 : 90 : run_cost += foreignrel->reltarget->cost.per_tuple * rows;
3250 : : }
3251 : : }
3078 rhaas@postgresql.org 3252 [ + + + + ]: 1091 : else if (IS_JOIN_REL(foreignrel))
3497 3253 : 112 : {
3254 : : PgFdwRelationInfo *fpinfo_i;
3255 : : PgFdwRelationInfo *fpinfo_o;
3256 : : QualCost join_cost;
3257 : : QualCost remote_conds_cost;
3258 : : double nrows;
3259 : :
3260 : : /* Use rows/width estimates made by the core code. */
2276 efujita@postgresql.o 3261 : 112 : rows = foreignrel->rows;
3262 : 112 : width = foreignrel->reltarget->width;
3263 : :
3264 : : /* For join we expect inner and outer relations set */
3497 rhaas@postgresql.org 3265 [ + - - + ]: 112 : Assert(fpinfo->innerrel && fpinfo->outerrel);
3266 : :
3267 : 112 : fpinfo_i = (PgFdwRelationInfo *) fpinfo->innerrel->fdw_private;
3268 : 112 : fpinfo_o = (PgFdwRelationInfo *) fpinfo->outerrel->fdw_private;
3269 : :
3270 : : /* Estimate of number of rows in cross product */
3271 : 112 : nrows = fpinfo_i->rows * fpinfo_o->rows;
3272 : :
3273 : : /*
3274 : : * Back into an estimate of the number of retrieved rows. Just in
3275 : : * case this is nuts, clamp to at most nrows.
3276 : : */
2276 efujita@postgresql.o 3277 : 112 : retrieved_rows = clamp_row_est(rows / fpinfo->local_conds_sel);
3497 rhaas@postgresql.org 3278 [ + + ]: 112 : retrieved_rows = Min(retrieved_rows, nrows);
3279 : :
3280 : : /*
3281 : : * The cost of foreign join is estimated as cost of generating
3282 : : * rows for the joining relations + cost for applying quals on the
3283 : : * rows.
3284 : : */
3285 : :
3286 : : /*
3287 : : * Calculate the cost of clauses pushed down to the foreign server
3288 : : */
3289 : 112 : cost_qual_eval(&remote_conds_cost, fpinfo->remote_conds, root);
3290 : : /* Calculate the cost of applying join clauses */
3291 : 112 : cost_qual_eval(&join_cost, fpinfo->joinclauses, root);
3292 : :
3293 : : /*
3294 : : * Startup cost includes startup cost of joining relations and the
3295 : : * startup cost for join and other clauses. We do not include the
3296 : : * startup cost specific to join strategy (e.g. setting up hash
3297 : : * tables) since we do not know what strategy the foreign server
3298 : : * is going to use.
3299 : : */
3300 : 112 : startup_cost = fpinfo_i->rel_startup_cost + fpinfo_o->rel_startup_cost;
3301 : 112 : startup_cost += join_cost.startup;
3302 : 112 : startup_cost += remote_conds_cost.startup;
3303 : 112 : startup_cost += fpinfo->local_conds_cost.startup;
3304 : :
3305 : : /*
3306 : : * Run time cost includes:
3307 : : *
3308 : : * 1. Run time cost (total_cost - startup_cost) of relations being
3309 : : * joined
3310 : : *
3311 : : * 2. Run time cost of applying join clauses on the cross product
3312 : : * of the joining relations.
3313 : : *
3314 : : * 3. Run time cost of applying pushed down other clauses on the
3315 : : * result of join
3316 : : *
3317 : : * 4. Run time cost of applying nonpushable other clauses locally
3318 : : * on the result fetched from the foreign server.
3319 : : */
3320 : 112 : run_cost = fpinfo_i->rel_total_cost - fpinfo_i->rel_startup_cost;
3321 : 112 : run_cost += fpinfo_o->rel_total_cost - fpinfo_o->rel_startup_cost;
3322 : 112 : run_cost += nrows * join_cost.per_tuple;
3323 : 112 : nrows = clamp_row_est(nrows * fpinfo->joinclause_sel);
3324 : 112 : run_cost += nrows * remote_conds_cost.per_tuple;
3325 : 112 : run_cost += fpinfo->local_conds_cost.per_tuple * retrieved_rows;
3326 : :
3327 : : /* Add in tlist eval cost for each output row */
2417 efujita@postgresql.o 3328 : 112 : startup_cost += foreignrel->reltarget->cost.startup;
3329 : 112 : run_cost += foreignrel->reltarget->cost.per_tuple * rows;
3330 : : }
3078 rhaas@postgresql.org 3331 [ + + + + ]: 979 : else if (IS_UPPER_REL(foreignrel))
3242 3332 : 98 : {
2312 efujita@postgresql.o 3333 : 98 : RelOptInfo *outerrel = fpinfo->outerrel;
3334 : : PgFdwRelationInfo *ofpinfo;
170 peter@eisentraut.org 3335 : 98 : AggClauseCosts aggcosts = {0};
3336 : : double input_rows;
3337 : : int numGroupCols;
3242 rhaas@postgresql.org 3338 : 98 : double numGroups = 1;
3339 : :
3340 : : /* The upper relation should have its outer relation set */
2312 efujita@postgresql.o 3341 [ - + ]: 98 : Assert(outerrel);
3342 : : /* and that outer relation should have its reltarget set */
3343 [ - + ]: 98 : Assert(outerrel->reltarget);
3344 : :
3345 : : /*
3346 : : * This cost model is mixture of costing done for sorted and
3347 : : * hashed aggregates in cost_agg(). We are not sure which
3348 : : * strategy will be considered at remote side, thus for
3349 : : * simplicity, we put all startup related costs in startup_cost
3350 : : * and all finalization and run cost are added in total_cost.
3351 : : */
3352 : :
3353 : 98 : ofpinfo = (PgFdwRelationInfo *) outerrel->fdw_private;
3354 : :
3355 : : /* Get rows from input rel */
3242 rhaas@postgresql.org 3356 : 98 : input_rows = ofpinfo->rows;
3357 : :
3358 : : /* Collect statistics about aggregates for estimating costs. */
3359 [ + + ]: 98 : if (root->parse->hasAggs)
3360 : : {
1747 heikki.linnakangas@i 3361 : 94 : get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
3362 : : }
3363 : :
3364 : : /* Get number of grouping columns and possible number of groups */
962 tgl@sss.pgh.pa.us 3365 : 98 : numGroupCols = list_length(root->processed_groupClause);
3242 rhaas@postgresql.org 3366 : 98 : numGroups = estimate_num_groups(root,
3367 : : get_sortgrouplist_exprs(root->processed_groupClause,
3368 : : fpinfo->grouped_tlist),
3369 : : input_rows, NULL, NULL);
3370 : :
3371 : : /*
3372 : : * Get the retrieved_rows and rows estimates. If there are HAVING
3373 : : * quals, account for their selectivity.
3374 : : */
1054 tgl@sss.pgh.pa.us 3375 [ + + ]: 98 : if (root->hasHavingQual)
3376 : : {
3377 : : /* Factor in the selectivity of the remotely-checked quals */
3378 : : retrieved_rows =
2468 efujita@postgresql.o 3379 : 14 : clamp_row_est(numGroups *
3380 : 14 : clauselist_selectivity(root,
3381 : : fpinfo->remote_conds,
3382 : : 0,
3383 : : JOIN_INNER,
3384 : : NULL));
3385 : : /* Factor in the selectivity of the locally-checked quals */
3386 : 14 : rows = clamp_row_est(retrieved_rows * fpinfo->local_conds_sel);
3387 : : }
3388 : : else
3389 : : {
3390 : 84 : rows = retrieved_rows = numGroups;
3391 : : }
3392 : :
3393 : : /* Use width estimate made by the core code. */
2276 3394 : 98 : width = foreignrel->reltarget->width;
3395 : :
3396 : : /*-----
3397 : : * Startup cost includes:
3398 : : * 1. Startup cost for underneath input relation, adjusted for
3399 : : * tlist replacement by apply_scanjoin_target_to_paths()
3400 : : * 2. Cost of performing aggregation, per cost_agg()
3401 : : *-----
3402 : : */
3242 rhaas@postgresql.org 3403 : 98 : startup_cost = ofpinfo->rel_startup_cost;
2312 efujita@postgresql.o 3404 : 98 : startup_cost += outerrel->reltarget->cost.startup;
3242 rhaas@postgresql.org 3405 : 98 : startup_cost += aggcosts.transCost.startup;
3406 : 98 : startup_cost += aggcosts.transCost.per_tuple * input_rows;
2401 tgl@sss.pgh.pa.us 3407 : 98 : startup_cost += aggcosts.finalCost.startup;
3242 rhaas@postgresql.org 3408 : 98 : startup_cost += (cpu_operator_cost * numGroupCols) * input_rows;
3409 : :
3410 : : /*-----
3411 : : * Run time cost includes:
3412 : : * 1. Run time cost of underneath input relation, adjusted for
3413 : : * tlist replacement by apply_scanjoin_target_to_paths()
3414 : : * 2. Run time cost of performing aggregation, per cost_agg()
3415 : : *-----
3416 : : */
3417 : 98 : run_cost = ofpinfo->rel_total_cost - ofpinfo->rel_startup_cost;
2312 efujita@postgresql.o 3418 : 98 : run_cost += outerrel->reltarget->cost.per_tuple * input_rows;
2401 tgl@sss.pgh.pa.us 3419 : 98 : run_cost += aggcosts.finalCost.per_tuple * numGroups;
3242 rhaas@postgresql.org 3420 : 98 : run_cost += cpu_tuple_cost * numGroups;
3421 : :
3422 : : /* Account for the eval cost of HAVING quals, if any */
1054 tgl@sss.pgh.pa.us 3423 [ + + ]: 98 : if (root->hasHavingQual)
3424 : : {
3425 : : QualCost remote_cost;
3426 : :
3427 : : /* Add in the eval cost of the remotely-checked quals */
2468 efujita@postgresql.o 3428 : 14 : cost_qual_eval(&remote_cost, fpinfo->remote_conds, root);
3429 : 14 : startup_cost += remote_cost.startup;
3430 : 14 : run_cost += remote_cost.per_tuple * numGroups;
3431 : : /* Add in the eval cost of the locally-checked quals */
3432 : 14 : startup_cost += fpinfo->local_conds_cost.startup;
3433 : 14 : run_cost += fpinfo->local_conds_cost.per_tuple * retrieved_rows;
3434 : : }
3435 : :
3436 : : /* Add in tlist eval cost for each output row */
2417 3437 : 98 : startup_cost += foreignrel->reltarget->cost.startup;
3438 : 98 : run_cost += foreignrel->reltarget->cost.per_tuple * rows;
3439 : : }
3440 : : else
3441 : : {
3442 : : Cost cpu_per_tuple;
3443 : :
3444 : : /* Use rows/width estimates made by set_baserel_size_estimates. */
2276 3445 : 881 : rows = foreignrel->rows;
3446 : 881 : width = foreignrel->reltarget->width;
3447 : :
3448 : : /*
3449 : : * Back into an estimate of the number of retrieved rows. Just in
3450 : : * case this is nuts, clamp to at most foreignrel->tuples.
3451 : : */
3452 : 881 : retrieved_rows = clamp_row_est(rows / fpinfo->local_conds_sel);
3242 rhaas@postgresql.org 3453 [ + + ]: 881 : retrieved_rows = Min(retrieved_rows, foreignrel->tuples);
3454 : :
3455 : : /*
3456 : : * Cost as though this were a seqscan, which is pessimistic. We
3457 : : * effectively imagine the local_conds are being evaluated
3458 : : * remotely, too.
3459 : : */
3460 : 881 : startup_cost = 0;
3461 : 881 : run_cost = 0;
3462 : 881 : run_cost += seq_page_cost * foreignrel->pages;
3463 : :
3464 : 881 : startup_cost += foreignrel->baserestrictcost.startup;
3465 : 881 : cpu_per_tuple = cpu_tuple_cost + foreignrel->baserestrictcost.per_tuple;
3466 : 881 : run_cost += cpu_per_tuple * foreignrel->tuples;
3467 : :
3468 : : /* Add in tlist eval cost for each output row */
2417 efujita@postgresql.o 3469 : 881 : startup_cost += foreignrel->reltarget->cost.startup;
3470 : 881 : run_cost += foreignrel->reltarget->cost.per_tuple * rows;
3471 : : }
3472 : :
3473 : : /*
3474 : : * Without remote estimates, we have no real way to estimate the cost
3475 : : * of generating sorted output. It could be free if the query plan
3476 : : * the remote side would have chosen generates properly-sorted output
3477 : : * anyway, but in most cases it will cost something. Estimate a value
3478 : : * high enough that we won't pick the sorted path when the ordering
3479 : : * isn't locally useful, but low enough that we'll err on the side of
3480 : : * pushing down the ORDER BY clause when it's useful to do so.
3481 : : */
3595 rhaas@postgresql.org 3482 [ + + ]: 1401 : if (pathkeys != NIL)
3483 : : {
2349 efujita@postgresql.o 3484 [ + + - + ]: 254 : if (IS_UPPER_REL(foreignrel))
3485 : : {
3486 [ + - - + ]: 30 : Assert(foreignrel->reloptkind == RELOPT_UPPER_REL &&
3487 : : fpinfo->stage == UPPERREL_GROUP_AGG);
3488 : :
3489 : : /*
3490 : : * We can only get here when this function is called from
3491 : : * add_foreign_ordered_paths() or add_foreign_final_paths();
3492 : : * in which cases, the passed-in fpextra should not be NULL.
3493 : : */
62 efujita@postgresql.o 3494 [ - + ]:GNC 30 : Assert(fpextra);
2349 efujita@postgresql.o 3495 :CBC 30 : adjust_foreign_grouping_path_cost(root, pathkeys,
3496 : : retrieved_rows, width,
3497 : : fpextra->limit_tuples,
3498 : : &disabled_nodes,
3499 : : &startup_cost, &run_cost);
3500 : : }
3501 : : else
3502 : : {
3503 : 224 : startup_cost *= DEFAULT_FDW_SORT_MULTIPLIER;
3504 : 224 : run_cost *= DEFAULT_FDW_SORT_MULTIPLIER;
3505 : : }
3506 : : }
3507 : :
4552 tgl@sss.pgh.pa.us 3508 : 1401 : total_cost = startup_cost + run_cost;
3509 : :
3510 : : /* Adjust the cost estimates if we have LIMIT */
2349 efujita@postgresql.o 3511 [ + + + + ]: 1401 : if (fpextra && fpextra->has_limit)
3512 : : {
3513 : 92 : adjust_limit_rows_costs(&rows, &startup_cost, &total_cost,
3514 : : fpextra->offset_est, fpextra->count_est);
3515 : 92 : retrieved_rows = rows;
3516 : : }
3517 : : }
3518 : :
3519 : : /*
3520 : : * If this includes the final sort step, the given target, which will be
3521 : : * applied to the resulting path, might have different expressions from
3522 : : * the foreignrel's reltarget (see make_sort_input_target()); adjust tlist
3523 : : * eval costs.
3524 : : */
3525 [ + + + + ]: 2686 : if (fpextra && fpextra->has_final_sort &&
3526 [ + + ]: 109 : fpextra->target != foreignrel->reltarget)
3527 : : {
3528 : 6 : QualCost oldcost = foreignrel->reltarget->cost;
3529 : 6 : QualCost newcost = fpextra->target->cost;
3530 : :
3531 : 6 : startup_cost += newcost.startup - oldcost.startup;
3532 : 6 : total_cost += newcost.startup - oldcost.startup;
3533 : 6 : total_cost += (newcost.per_tuple - oldcost.per_tuple) * rows;
3534 : : }
3535 : :
3536 : : /*
3537 : : * Cache the retrieved rows and cost estimates for scans, joins, or
3538 : : * groupings without any parameterization, pathkeys, or additional
3539 : : * post-scan/join-processing steps, before adding the costs for
3540 : : * transferring data from the foreign server. These estimates are useful
3541 : : * for costing remote joins involving this relation or costing other
3542 : : * remote operations on this relation such as remote sorts and remote
3543 : : * LIMIT restrictions, when the costs can not be obtained from the foreign
3544 : : * server. This function will be called at least once for every foreign
3545 : : * relation without any parameterization, pathkeys, or additional
3546 : : * post-scan/join-processing steps.
3547 : : */
3548 [ + + + + : 2686 : if (pathkeys == NIL && param_join_conds == NIL && fpextra == NULL)
+ + ]
3549 : : {
2276 3550 : 1641 : fpinfo->retrieved_rows = retrieved_rows;
3468 rhaas@postgresql.org 3551 : 1641 : fpinfo->rel_startup_cost = startup_cost;
3552 : 1641 : fpinfo->rel_total_cost = total_cost;
3553 : : }
3554 : :
3555 : : /*
3556 : : * Add some additional cost factors to account for connection overhead
3557 : : * (fdw_startup_cost), transferring data across the network
3558 : : * (fdw_tuple_cost per retrieved row), and local manipulation of the data
3559 : : * (cpu_tuple_cost per retrieved row).
3560 : : */
4552 tgl@sss.pgh.pa.us 3561 : 2686 : startup_cost += fpinfo->fdw_startup_cost;
3562 : 2686 : total_cost += fpinfo->fdw_startup_cost;
3563 : 2686 : total_cost += fpinfo->fdw_tuple_cost * retrieved_rows;
3564 : 2686 : total_cost += cpu_tuple_cost * retrieved_rows;
3565 : :
3566 : : /*
3567 : : * If we have LIMIT, we should prefer performing the restriction remotely
3568 : : * rather than locally, as the former avoids extra row fetches from the
3569 : : * remote that the latter might cause. But since the core code doesn't
3570 : : * account for such fetches when estimating the costs of the local
3571 : : * restriction (see create_limit_path()), there would be no difference
3572 : : * between the costs of the local restriction and the costs of the remote
3573 : : * restriction estimated above if we don't use remote estimates (except
3574 : : * for the case where the foreignrel is a grouping relation, the given
3575 : : * pathkeys is not NIL, and the effects of a bounded sort for that rel is
3576 : : * accounted for in costing the remote restriction). Tweak the costs of
3577 : : * the remote restriction to ensure we'll prefer it if LIMIT is a useful
3578 : : * one.
3579 : : */
2349 efujita@postgresql.o 3580 [ + + + + ]: 2686 : if (!fpinfo->use_remote_estimate &&
3581 [ + + ]: 122 : fpextra && fpextra->has_limit &&
3582 [ + - ]: 92 : fpextra->limit_tuples > 0 &&
3583 [ + + ]: 92 : fpextra->limit_tuples < fpinfo->rows)
3584 : : {
3585 [ - + ]: 86 : Assert(fpinfo->rows > 0);
3586 : 86 : total_cost -= (total_cost - startup_cost) * 0.05 *
3587 : 86 : (fpinfo->rows - fpextra->limit_tuples) / fpinfo->rows;
3588 : : }
3589 : :
3590 : : /* Return results. */
4552 tgl@sss.pgh.pa.us 3591 : 2686 : *p_rows = rows;
3592 : 2686 : *p_width = width;
381 rhaas@postgresql.org 3593 : 2686 : *p_disabled_nodes = disabled_nodes;
4552 tgl@sss.pgh.pa.us 3594 : 2686 : *p_startup_cost = startup_cost;
3595 : 2686 : *p_total_cost = total_cost;
3596 : 2686 : }
3597 : :
3598 : : /*
3599 : : * Estimate costs of executing a SQL statement remotely.
3600 : : * The given "sql" must be an EXPLAIN command.
3601 : : */
3602 : : static void
4580 3603 : 1285 : get_remote_estimate(const char *sql, PGconn *conn,
3604 : : double *rows, int *width,
3605 : : Cost *startup_cost, Cost *total_cost)
3606 : : {
3607 : : PGresult *res;
3608 : : char *line;
3609 : : char *p;
3610 : : int n;
3611 : :
3612 : : /*
3613 : : * Execute EXPLAIN remotely.
3614 : : */
43 tgl@sss.pgh.pa.us 3615 :GNC 1285 : res = pgfdw_exec_query(conn, sql, NULL);
3616 [ - + ]: 1285 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 3617 :UNC 0 : pgfdw_report_error(res, conn, sql);
3618 : :
3619 : : /*
3620 : : * Extract cost numbers for topmost plan node. Note we search for a left
3621 : : * paren from the end of the line to avoid being confused by other uses of
3622 : : * parentheses.
3623 : : */
43 tgl@sss.pgh.pa.us 3624 :GNC 1285 : line = PQgetvalue(res, 0, 0);
3625 : 1285 : p = strrchr(line, '(');
3626 [ - + ]: 1285 : if (p == NULL)
43 tgl@sss.pgh.pa.us 3627 [ # # ]:UNC 0 : elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
43 tgl@sss.pgh.pa.us 3628 :GNC 1285 : n = sscanf(p, "(cost=%lf..%lf rows=%lf width=%d)",
3629 : : startup_cost, total_cost, rows, width);
3630 [ - + ]: 1285 : if (n != 4)
43 tgl@sss.pgh.pa.us 3631 [ # # ]:UNC 0 : elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
43 tgl@sss.pgh.pa.us 3632 :GNC 1285 : PQclear(res);
4580 tgl@sss.pgh.pa.us 3633 :CBC 1285 : }
3634 : :
3635 : : /*
3636 : : * Adjust the cost estimates of a foreign grouping path to include the cost of
3637 : : * generating properly-sorted output.
3638 : : */
3639 : : static void
2349 efujita@postgresql.o 3640 : 30 : adjust_foreign_grouping_path_cost(PlannerInfo *root,
3641 : : List *pathkeys,
3642 : : double retrieved_rows,
3643 : : double width,
3644 : : double limit_tuples,
3645 : : int *p_disabled_nodes,
3646 : : Cost *p_startup_cost,
3647 : : Cost *p_run_cost)
3648 : : {
3649 : : /*
3650 : : * If the GROUP BY clause isn't sort-able, the plan chosen by the remote
3651 : : * side is unlikely to generate properly-sorted output, so it would need
3652 : : * an explicit sort; adjust the given costs with cost_sort(). Likewise,
3653 : : * if the GROUP BY clause is sort-able but isn't a superset of the given
3654 : : * pathkeys, adjust the costs with that function. Otherwise, adjust the
3655 : : * costs by applying the same heuristic as for the scan or join case.
3656 : : */
962 tgl@sss.pgh.pa.us 3657 [ + - ]: 30 : if (!grouping_is_sortable(root->processed_groupClause) ||
2349 efujita@postgresql.o 3658 [ + + ]: 30 : !pathkeys_contained_in(pathkeys, root->group_pathkeys))
3659 : 22 : {
3660 : : Path sort_path; /* dummy for result of cost_sort */
3661 : :
3662 : 22 : cost_sort(&sort_path,
3663 : : root,
3664 : : pathkeys,
3665 : : 0,
3666 : 22 : *p_startup_cost + *p_run_cost,
3667 : : retrieved_rows,
3668 : : width,
3669 : : 0.0,
3670 : : work_mem,
3671 : : limit_tuples);
3672 : :
3673 : 22 : *p_startup_cost = sort_path.startup_cost;
3674 : 22 : *p_run_cost = sort_path.total_cost - sort_path.startup_cost;
3675 : : }
3676 : : else
3677 : : {
3678 : : /*
3679 : : * The default extra cost seems too large for foreign-grouping cases;
3680 : : * add 1/4th of that default.
3681 : : */
3682 : 8 : double sort_multiplier = 1.0 + (DEFAULT_FDW_SORT_MULTIPLIER
3683 : : - 1.0) * 0.25;
3684 : :
3685 : 8 : *p_startup_cost *= sort_multiplier;
3686 : 8 : *p_run_cost *= sort_multiplier;
3687 : : }
3688 : 30 : }
3689 : :
3690 : : /*
3691 : : * Detect whether we want to process an EquivalenceClass member.
3692 : : *
3693 : : * This is a callback for use by generate_implied_equalities_for_column.
3694 : : */
3695 : : static bool
4552 tgl@sss.pgh.pa.us 3696 : 298 : ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
3697 : : EquivalenceClass *ec, EquivalenceMember *em,
3698 : : void *arg)
3699 : : {
3700 : 298 : ec_member_foreign_arg *state = (ec_member_foreign_arg *) arg;
3701 : 298 : Expr *expr = em->em_expr;
3702 : :
3703 : : /*
3704 : : * If we've identified what we're processing in the current scan, we only
3705 : : * want to match that expression.
3706 : : */
3707 [ - + ]: 298 : if (state->current != NULL)
4552 tgl@sss.pgh.pa.us 3708 :UBC 0 : return equal(expr, state->current);
3709 : :
3710 : : /*
3711 : : * Otherwise, ignore anything we've already processed.
3712 : : */
4552 tgl@sss.pgh.pa.us 3713 [ + + ]:CBC 298 : if (list_member(state->already_used, expr))
3714 : 157 : return false;
3715 : :
3716 : : /* This is the new target to process. */
3717 : 141 : state->current = expr;
3718 : 141 : return true;
3719 : : }
3720 : :
3721 : : /*
3722 : : * Create cursor for node's query with current parameter values.
3723 : : */
3724 : : static void
4580 3725 : 829 : create_cursor(ForeignScanState *node)
3726 : : {
4563 3727 : 829 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
4552 3728 : 829 : ExprContext *econtext = node->ss.ps.ps_ExprContext;
4563 3729 : 829 : int numParams = fsstate->numParams;
3730 : 829 : const char **values = fsstate->param_values;
3731 : 829 : PGconn *conn = fsstate->conn;
3732 : : StringInfoData buf;
3733 : : PGresult *res;
3734 : :
3735 : : /* First, process a pending asynchronous request, if any. */
1620 efujita@postgresql.o 3736 [ + + ]: 829 : if (fsstate->conn_state->pendingAreq)
3737 : 1 : process_pending_request(fsstate->conn_state->pendingAreq);
3738 : :
3739 : : /*
3740 : : * Construct array of query parameter values in text format. We do the
3741 : : * conversions in the short-lived per-tuple context, so as not to cause a
3742 : : * memory leak over repeated scans.
3743 : : */
4552 tgl@sss.pgh.pa.us 3744 [ + + ]: 829 : if (numParams > 0)
3745 : : {
3746 : : MemoryContext oldcontext;
3747 : :
3748 : 347 : oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
3749 : :
3459 rhaas@postgresql.org 3750 : 347 : process_query_params(econtext,
3751 : : fsstate->param_flinfo,
3752 : : fsstate->param_exprs,
3753 : : values);
3754 : :
4552 tgl@sss.pgh.pa.us 3755 : 347 : MemoryContextSwitchTo(oldcontext);
3756 : : }
3757 : :
3758 : : /* Construct the DECLARE CURSOR command */
4580 3759 : 829 : initStringInfo(&buf);
3760 : 829 : appendStringInfo(&buf, "DECLARE c%u CURSOR FOR\n%s",
3761 : : fsstate->cursor_number, fsstate->query);
3762 : :
3763 : : /*
3764 : : * Notice that we pass NULL for paramTypes, thus forcing the remote server
3765 : : * to infer types for all parameters. Since we explicitly cast every
3766 : : * parameter (see deparse.c), the "inference" is trivial and will produce
3767 : : * the desired result. This allows us to avoid assuming that the remote
3768 : : * server has the same OIDs we do for the parameters' types.
3769 : : */
3425 rhaas@postgresql.org 3770 [ - + ]: 829 : if (!PQsendQueryParams(conn, buf.data, numParams,
3771 : : NULL, values, NULL, NULL, 0))
39 tgl@sss.pgh.pa.us 3772 :UNC 0 : pgfdw_report_error(NULL, conn, buf.data);
3773 : :
3774 : : /*
3775 : : * Get the result, and check for success.
3776 : : */
607 noah@leadboat.com 3777 :CBC 829 : res = pgfdw_get_result(conn);
4580 tgl@sss.pgh.pa.us 3778 [ + + ]: 829 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 3779 :GNC 3 : pgfdw_report_error(res, conn, fsstate->query);
4580 tgl@sss.pgh.pa.us 3780 :CBC 826 : PQclear(res);
3781 : :
3782 : : /* Mark the cursor as created, and show no tuples have been retrieved */
4563 3783 : 826 : fsstate->cursor_exists = true;
3784 : 826 : fsstate->tuples = NULL;
3785 : 826 : fsstate->num_tuples = 0;
3786 : 826 : fsstate->next_tuple = 0;
3787 : 826 : fsstate->fetch_ct_2 = 0;
3788 : 826 : fsstate->eof_reached = false;
3789 : :
3790 : : /* Clean up */
4580 3791 : 826 : pfree(buf.data);
3792 : 826 : }
3793 : :
3794 : : /*
3795 : : * Fetch some more rows from the node's cursor.
3796 : : */
3797 : : static void
3798 : 1497 : fetch_more_data(ForeignScanState *node)
3799 : : {
4563 3800 : 1497 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
43 tgl@sss.pgh.pa.us 3801 :GNC 1497 : PGconn *conn = fsstate->conn;
3802 : : PGresult *res;
3803 : : int numrows;
3804 : : int i;
3805 : : MemoryContext oldcontext;
3806 : :
3807 : : /*
3808 : : * We'll store the tuples in the batch_cxt. First, flush the previous
3809 : : * batch.
3810 : : */
4563 tgl@sss.pgh.pa.us 3811 :CBC 1497 : fsstate->tuples = NULL;
3812 : 1497 : MemoryContextReset(fsstate->batch_cxt);
3813 : 1497 : oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt);
3814 : :
43 tgl@sss.pgh.pa.us 3815 [ + + ]:GNC 1497 : if (fsstate->async_capable)
3816 : : {
3817 [ - + ]: 158 : Assert(fsstate->conn_state->pendingAreq);
3818 : :
3819 : : /*
3820 : : * The query was already sent by an earlier call to
3821 : : * fetch_more_data_begin. So now we just fetch the result.
3822 : : */
3823 : 158 : res = pgfdw_get_result(conn);
3824 : : /* On error, report the original query, not the FETCH. */
3825 [ - + ]: 158 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 3826 :UNC 0 : pgfdw_report_error(res, conn, fsstate->query);
3827 : :
3828 : : /* Reset per-connection state */
43 tgl@sss.pgh.pa.us 3829 :GNC 158 : fsstate->conn_state->pendingAreq = NULL;
3830 : : }
3831 : : else
3832 : : {
3833 : : char sql[64];
3834 : :
3835 : : /* This is a regular synchronous fetch. */
3836 : 1339 : snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
3837 : : fsstate->fetch_size, fsstate->cursor_number);
3838 : :
3839 : 1339 : res = pgfdw_exec_query(conn, sql, fsstate->conn_state);
3840 : : /* On error, report the original query, not the FETCH. */
3841 [ + + ]: 1338 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 3842 : 1 : pgfdw_report_error(res, conn, fsstate->query);
3843 : : }
3844 : :
3845 : : /* Convert the data into HeapTuples */
43 3846 : 1495 : numrows = PQntuples(res);
3847 : 1495 : fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple));
3848 : 1495 : fsstate->num_tuples = numrows;
3849 : 1495 : fsstate->next_tuple = 0;
3850 : :
3851 [ + + ]: 72721 : for (i = 0; i < numrows; i++)
3852 : : {
3853 [ - + ]: 71230 : Assert(IsA(node->ss.ps.plan, ForeignScan));
3854 : :
3855 : 71226 : fsstate->tuples[i] =
3856 : 71230 : make_tuple_from_result_row(res, i,
3857 : : fsstate->rel,
3858 : : fsstate->attinmeta,
3859 : : fsstate->retrieved_attrs,
3860 : : node,
3861 : : fsstate->temp_cxt);
3862 : : }
3863 : :
3864 : : /* Update fetch_ct_2 */
3865 [ + + ]: 1491 : if (fsstate->fetch_ct_2 < 2)
3866 : 939 : fsstate->fetch_ct_2++;
3867 : :
3868 : : /* Must be EOF if we didn't get as many tuples as we asked for. */
3869 : 1491 : fsstate->eof_reached = (numrows < fsstate->fetch_size);
3870 : :
3871 : 1491 : PQclear(res);
3872 : :
4580 tgl@sss.pgh.pa.us 3873 :CBC 1491 : MemoryContextSwitchTo(oldcontext);
3874 : 1491 : }
3875 : :
3876 : : /*
3877 : : * Force assorted GUC parameters to settings that ensure that we'll output
3878 : : * data values in a form that is unambiguous to the remote server.
3879 : : *
3880 : : * This is rather expensive and annoying to do once per row, but there's
3881 : : * little choice if we want to be sure values are transmitted accurately;
3882 : : * we can't leave the settings in place between rows for fear of affecting
3883 : : * user-visible computations.
3884 : : *
3885 : : * We use the equivalent of a function SET option to allow the settings to
3886 : : * persist only until the caller calls reset_transmission_modes(). If an
3887 : : * error is thrown in between, guc.c will take care of undoing the settings.
3888 : : *
3889 : : * The return value is the nestlevel that must be passed to
3890 : : * reset_transmission_modes() to undo things.
3891 : : */
3892 : : int
4562 3893 : 4202 : set_transmission_modes(void)
3894 : : {
3895 : 4202 : int nestlevel = NewGUCNestLevel();
3896 : :
3897 : : /*
3898 : : * The values set here should match what pg_dump does. See also
3899 : : * configure_remote_session in connection.c.
3900 : : */
3901 [ + + ]: 4202 : if (DateStyle != USE_ISO_DATES)
3902 : 4200 : (void) set_config_option("datestyle", "ISO",
3903 : : PGC_USERSET, PGC_S_SESSION,
3904 : : GUC_ACTION_SAVE, true, 0, false);
3905 [ + + ]: 4202 : if (IntervalStyle != INTSTYLE_POSTGRES)
3906 : 4200 : (void) set_config_option("intervalstyle", "postgres",
3907 : : PGC_USERSET, PGC_S_SESSION,
3908 : : GUC_ACTION_SAVE, true, 0, false);
3909 [ + + ]: 4202 : if (extra_float_digits < 3)
3910 : 4200 : (void) set_config_option("extra_float_digits", "3",
3911 : : PGC_USERSET, PGC_S_SESSION,
3912 : : GUC_ACTION_SAVE, true, 0, false);
3913 : :
3914 : : /*
3915 : : * In addition force restrictive search_path, in case there are any
3916 : : * regproc or similar constants to be printed.
3917 : : */
1147 3918 : 4202 : (void) set_config_option("search_path", "pg_catalog",
3919 : : PGC_USERSET, PGC_S_SESSION,
3920 : : GUC_ACTION_SAVE, true, 0, false);
3921 : :
4562 3922 : 4202 : return nestlevel;
3923 : : }
3924 : :
3925 : : /*
3926 : : * Undo the effects of set_transmission_modes().
3927 : : */
3928 : : void
3929 : 4202 : reset_transmission_modes(int nestlevel)
3930 : : {
3931 : 4202 : AtEOXact_GUC(true, nestlevel);
3932 : 4202 : }
3933 : :
3934 : : /*
3935 : : * Utility routine to close a cursor.
3936 : : */
3937 : : static void
1620 efujita@postgresql.o 3938 : 498 : close_cursor(PGconn *conn, unsigned int cursor_number,
3939 : : PgFdwConnState *conn_state)
3940 : : {
3941 : : char sql[64];
3942 : : PGresult *res;
3943 : :
4580 tgl@sss.pgh.pa.us 3944 : 498 : snprintf(sql, sizeof(sql), "CLOSE c%u", cursor_number);
1620 efujita@postgresql.o 3945 : 498 : res = pgfdw_exec_query(conn, sql, conn_state);
4580 tgl@sss.pgh.pa.us 3946 [ - + ]: 498 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 3947 :UNC 0 : pgfdw_report_error(res, conn, sql);
4580 tgl@sss.pgh.pa.us 3948 :CBC 498 : PQclear(res);
3949 : 498 : }
3950 : :
3951 : : /*
3952 : : * create_foreign_modify
3953 : : * Construct an execution state of a foreign insert/update/delete
3954 : : * operation
3955 : : */
3956 : : static PgFdwModifyState *
2710 rhaas@postgresql.org 3957 : 182 : create_foreign_modify(EState *estate,
3958 : : RangeTblEntry *rte,
3959 : : ResultRelInfo *resultRelInfo,
3960 : : CmdType operation,
3961 : : Plan *subplan,
3962 : : char *query,
3963 : : List *target_attrs,
3964 : : int values_end,
3965 : : bool has_returning,
3966 : : List *retrieved_attrs)
3967 : : {
3968 : : PgFdwModifyState *fmstate;
3969 : 182 : Relation rel = resultRelInfo->ri_RelationDesc;
3970 : 182 : TupleDesc tupdesc = RelationGetDescr(rel);
3971 : : Oid userid;
3972 : : ForeignTable *table;
3973 : : UserMapping *user;
3974 : : AttrNumber n_params;
3975 : : Oid typefnoid;
3976 : : bool isvarlena;
3977 : : ListCell *lc;
3978 : :
3979 : : /* Begin constructing PgFdwModifyState. */
3980 : 182 : fmstate = (PgFdwModifyState *) palloc0(sizeof(PgFdwModifyState));
3981 : 182 : fmstate->rel = rel;
3982 : :
3983 : : /* Identify which user to do the remote access as. */
1005 alvherre@alvh.no-ip. 3984 : 182 : userid = ExecGetResultRelCheckAsUser(resultRelInfo, estate);
3985 : :
3986 : : /* Get info about foreign table. */
2710 rhaas@postgresql.org 3987 : 182 : table = GetForeignTable(RelationGetRelid(rel));
3988 : 182 : user = GetUserMapping(userid, table->serverid);
3989 : :
3990 : : /* Open connection; report that we'll create a prepared statement. */
1620 efujita@postgresql.o 3991 : 182 : fmstate->conn = GetConnection(user, true, &fmstate->conn_state);
2710 rhaas@postgresql.org 3992 : 182 : fmstate->p_name = NULL; /* prepared statement not made yet */
3993 : :
3994 : : /* Set up remote query information. */
3995 : 182 : fmstate->query = query;
1690 tomas.vondra@postgre 3996 [ + + ]: 182 : if (operation == CMD_INSERT)
3997 : : {
1583 3998 : 133 : fmstate->query = pstrdup(fmstate->query);
1690 3999 : 133 : fmstate->orig_query = pstrdup(fmstate->query);
4000 : : }
2710 rhaas@postgresql.org 4001 : 182 : fmstate->target_attrs = target_attrs;
1690 tomas.vondra@postgre 4002 : 182 : fmstate->values_end = values_end;
2710 rhaas@postgresql.org 4003 : 182 : fmstate->has_returning = has_returning;
4004 : 182 : fmstate->retrieved_attrs = retrieved_attrs;
4005 : :
4006 : : /* Create context for per-tuple temp workspace. */
4007 : 182 : fmstate->temp_cxt = AllocSetContextCreate(estate->es_query_cxt,
4008 : : "postgres_fdw temporary data",
4009 : : ALLOCSET_SMALL_SIZES);
4010 : :
4011 : : /* Prepare for input conversion of RETURNING results. */
4012 [ + + ]: 182 : if (fmstate->has_returning)
4013 : 62 : fmstate->attinmeta = TupleDescGetAttInMetadata(tupdesc);
4014 : :
4015 : : /* Prepare for output conversion of parameters used in prepared stmt. */
4016 : 182 : n_params = list_length(fmstate->target_attrs) + 1;
4017 : 182 : fmstate->p_flinfo = (FmgrInfo *) palloc0(sizeof(FmgrInfo) * n_params);
4018 : 182 : fmstate->p_nums = 0;
4019 : :
4020 [ + + + + ]: 182 : if (operation == CMD_UPDATE || operation == CMD_DELETE)
4021 : : {
4022 [ - + ]: 49 : Assert(subplan != NULL);
4023 : :
4024 : : /* Find the ctid resjunk column in the subplan's result */
4025 : 49 : fmstate->ctidAttno = ExecFindJunkAttributeInTlist(subplan->targetlist,
4026 : : "ctid");
4027 [ - + ]: 49 : if (!AttributeNumberIsValid(fmstate->ctidAttno))
2710 rhaas@postgresql.org 4028 [ # # ]:UBC 0 : elog(ERROR, "could not find junk ctid column");
4029 : :
4030 : : /* First transmittable parameter will be ctid */
2710 rhaas@postgresql.org 4031 :CBC 49 : getTypeOutputInfo(TIDOID, &typefnoid, &isvarlena);
4032 : 49 : fmgr_info(typefnoid, &fmstate->p_flinfo[fmstate->p_nums]);
4033 : 49 : fmstate->p_nums++;
4034 : : }
4035 : :
4036 [ + + + + ]: 182 : if (operation == CMD_INSERT || operation == CMD_UPDATE)
4037 : : {
4038 : : /* Set up for remaining transmittable parameters */
4039 [ + + + + : 568 : foreach(lc, fmstate->target_attrs)
+ + ]
4040 : : {
4041 : 399 : int attnum = lfirst_int(lc);
4042 : 399 : Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1);
4043 : :
4044 [ - + ]: 399 : Assert(!attr->attisdropped);
4045 : :
4046 : : /* Ignore generated columns; they are set to DEFAULT */
1493 efujita@postgresql.o 4047 [ + + ]: 399 : if (attr->attgenerated)
4048 : 8 : continue;
2710 rhaas@postgresql.org 4049 : 391 : getTypeOutputInfo(attr->atttypid, &typefnoid, &isvarlena);
4050 : 391 : fmgr_info(typefnoid, &fmstate->p_flinfo[fmstate->p_nums]);
4051 : 391 : fmstate->p_nums++;
4052 : : }
4053 : : }
4054 : :
4055 [ - + ]: 182 : Assert(fmstate->p_nums <= n_params);
4056 : :
4057 : : /* Set batch_size from foreign server/table options. */
1690 tomas.vondra@postgre 4058 [ + + ]: 182 : if (operation == CMD_INSERT)
4059 : 133 : fmstate->batch_size = get_batch_size_option(rel);
4060 : :
4061 : 182 : fmstate->num_slots = 1;
4062 : :
4063 : : /* Initialize auxiliary state */
2327 efujita@postgresql.o 4064 : 182 : fmstate->aux_fmstate = NULL;
4065 : :
2710 rhaas@postgresql.org 4066 : 182 : return fmstate;
4067 : : }
4068 : :
4069 : : /*
4070 : : * execute_foreign_modify
4071 : : * Perform foreign-table modification as required, and fetch RETURNING
4072 : : * result if any. (This is the shared guts of postgresExecForeignInsert,
4073 : : * postgresExecForeignBatchInsert, postgresExecForeignUpdate, and
4074 : : * postgresExecForeignDelete.)
4075 : : */
4076 : : static TupleTableSlot **
2424 efujita@postgresql.o 4077 : 1052 : execute_foreign_modify(EState *estate,
4078 : : ResultRelInfo *resultRelInfo,
4079 : : CmdType operation,
4080 : : TupleTableSlot **slots,
4081 : : TupleTableSlot **planSlots,
4082 : : int *numSlots)
4083 : : {
4084 : 1052 : PgFdwModifyState *fmstate = (PgFdwModifyState *) resultRelInfo->ri_FdwState;
2403 tgl@sss.pgh.pa.us 4085 : 1052 : ItemPointer ctid = NULL;
4086 : : const char **p_values;
4087 : : PGresult *res;
4088 : : int n_rows;
4089 : : StringInfoData sql;
4090 : :
4091 : : /* The operation should be INSERT, UPDATE, or DELETE */
2424 efujita@postgresql.o 4092 [ + + + + : 1052 : Assert(operation == CMD_INSERT ||
- + ]
4093 : : operation == CMD_UPDATE ||
4094 : : operation == CMD_DELETE);
4095 : :
4096 : : /* First, process a pending asynchronous request, if any. */
1620 4097 [ + + ]: 1052 : if (fmstate->conn_state->pendingAreq)
4098 : 1 : process_pending_request(fmstate->conn_state->pendingAreq);
4099 : :
4100 : : /*
4101 : : * If the existing query was deparsed and prepared for a different number
4102 : : * of rows, rebuild it for the proper number.
4103 : : */
1690 tomas.vondra@postgre 4104 [ + + + + ]: 1052 : if (operation == CMD_INSERT && fmstate->num_slots != *numSlots)
4105 : : {
4106 : : /* Destroy the prepared statement created previously */
4107 [ + + ]: 26 : if (fmstate->p_name)
4108 : 11 : deallocate_query(fmstate);
4109 : :
4110 : : /* Build INSERT string with numSlots records in its VALUES clause. */
4111 : 26 : initStringInfo(&sql);
1493 efujita@postgresql.o 4112 : 26 : rebuildInsertSql(&sql, fmstate->rel,
4113 : : fmstate->orig_query, fmstate->target_attrs,
4114 : : fmstate->values_end, fmstate->p_nums,
4115 : 26 : *numSlots - 1);
1690 tomas.vondra@postgre 4116 : 26 : pfree(fmstate->query);
4117 : 26 : fmstate->query = sql.data;
4118 : 26 : fmstate->num_slots = *numSlots;
4119 : : }
4120 : :
4121 : : /* Set up the prepared statement on the remote server, if we didn't yet */
2424 efujita@postgresql.o 4122 [ + + ]: 1052 : if (!fmstate->p_name)
4123 : 187 : prepare_foreign_modify(fmstate);
4124 : :
4125 : : /*
4126 : : * For UPDATE/DELETE, get the ctid that was passed up as a resjunk column
4127 : : */
4128 [ + + + + ]: 1052 : if (operation == CMD_UPDATE || operation == CMD_DELETE)
4129 : : {
4130 : : Datum datum;
4131 : : bool isNull;
4132 : :
1690 tomas.vondra@postgre 4133 : 118 : datum = ExecGetJunkAttribute(planSlots[0],
2424 efujita@postgresql.o 4134 : 118 : fmstate->ctidAttno,
4135 : : &isNull);
4136 : : /* shouldn't ever get a null result... */
4137 [ - + ]: 118 : if (isNull)
2424 efujita@postgresql.o 4138 [ # # ]:UBC 0 : elog(ERROR, "ctid is NULL");
2424 efujita@postgresql.o 4139 :CBC 118 : ctid = (ItemPointer) DatumGetPointer(datum);
4140 : : }
4141 : :
4142 : : /* Convert parameters needed by prepared statement to text form */
1690 tomas.vondra@postgre 4143 : 1052 : p_values = convert_prep_stmt_params(fmstate, ctid, slots, *numSlots);
4144 : :
4145 : : /*
4146 : : * Execute the prepared statement.
4147 : : */
2424 efujita@postgresql.o 4148 [ - + ]: 1052 : if (!PQsendQueryPrepared(fmstate->conn,
4149 : 1052 : fmstate->p_name,
1690 tomas.vondra@postgre 4150 : 1052 : fmstate->p_nums * (*numSlots),
4151 : : p_values,
4152 : : NULL,
4153 : : NULL,
4154 : : 0))
39 tgl@sss.pgh.pa.us 4155 :UNC 0 : pgfdw_report_error(NULL, fmstate->conn, fmstate->query);
4156 : :
4157 : : /*
4158 : : * Get the result, and check for success.
4159 : : */
607 noah@leadboat.com 4160 :CBC 1052 : res = pgfdw_get_result(fmstate->conn);
2424 efujita@postgresql.o 4161 [ + + ]: 2104 : if (PQresultStatus(res) !=
4162 [ + + ]: 1052 : (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
39 tgl@sss.pgh.pa.us 4163 :GNC 5 : pgfdw_report_error(res, fmstate->conn, fmstate->query);
4164 : :
4165 : : /* Check number of rows affected, and fetch RETURNING tuple if any */
2424 efujita@postgresql.o 4166 [ + + ]:CBC 1047 : if (fmstate->has_returning)
4167 : : {
1690 tomas.vondra@postgre 4168 [ - + ]: 108 : Assert(*numSlots == 1);
2424 efujita@postgresql.o 4169 : 108 : n_rows = PQntuples(res);
4170 [ + + ]: 108 : if (n_rows > 0)
1690 tomas.vondra@postgre 4171 : 107 : store_returning_result(fmstate, slots[0], res);
4172 : : }
4173 : : else
2424 efujita@postgresql.o 4174 : 939 : n_rows = atoi(PQcmdTuples(res));
4175 : :
4176 : : /* And clean up */
4177 : 1047 : PQclear(res);
4178 : :
4179 : 1047 : MemoryContextReset(fmstate->temp_cxt);
4180 : :
1690 tomas.vondra@postgre 4181 : 1047 : *numSlots = n_rows;
4182 : :
4183 : : /*
4184 : : * Return NULL if nothing was inserted/updated/deleted on the remote end
4185 : : */
4186 [ + + ]: 1047 : return (n_rows > 0) ? slots : NULL;
4187 : : }
4188 : :
4189 : : /*
4190 : : * prepare_foreign_modify
4191 : : * Establish a prepared statement for execution of INSERT/UPDATE/DELETE
4192 : : */
4193 : : static void
4563 tgl@sss.pgh.pa.us 4194 : 187 : prepare_foreign_modify(PgFdwModifyState *fmstate)
4195 : : {
4196 : : char prep_name[NAMEDATALEN];
4197 : : char *p_name;
4198 : : PGresult *res;
4199 : :
4200 : : /*
4201 : : * The caller would already have processed a pending asynchronous request
4202 : : * if any, so no need to do it here.
4203 : : */
4204 : :
4205 : : /* Construct name we'll use for the prepared statement. */
4206 : 187 : snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u",
4207 : : GetPrepStmtNumber(fmstate->conn));
4208 : 187 : p_name = pstrdup(prep_name);
4209 : :
4210 : : /*
4211 : : * We intentionally do not specify parameter types here, but leave the
4212 : : * remote server to derive them by default. This avoids possible problems
4213 : : * with the remote server using different type OIDs than we do. All of
4214 : : * the prepared statements we use in this module are simple enough that
4215 : : * the remote server will make the right choices.
4216 : : */
3425 rhaas@postgresql.org 4217 [ - + ]: 187 : if (!PQsendPrepare(fmstate->conn,
4218 : : p_name,
4219 : 187 : fmstate->query,
4220 : : 0,
4221 : : NULL))
39 tgl@sss.pgh.pa.us 4222 :UNC 0 : pgfdw_report_error(NULL, fmstate->conn, fmstate->query);
4223 : :
4224 : : /*
4225 : : * Get the result, and check for success.
4226 : : */
607 noah@leadboat.com 4227 :CBC 187 : res = pgfdw_get_result(fmstate->conn);
4563 tgl@sss.pgh.pa.us 4228 [ - + ]: 187 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 4229 :UNC 0 : pgfdw_report_error(res, fmstate->conn, fmstate->query);
4563 tgl@sss.pgh.pa.us 4230 :CBC 187 : PQclear(res);
4231 : :
4232 : : /* This action shows that the prepare has been done. */
4233 : 187 : fmstate->p_name = p_name;
4234 : 187 : }
4235 : :
4236 : : /*
4237 : : * convert_prep_stmt_params
4238 : : * Create array of text strings representing parameter values
4239 : : *
4240 : : * tupleid is ctid to send, or NULL if none
4241 : : * slot is slot to get remaining parameters from, or NULL if none
4242 : : *
4243 : : * Data is constructed in temp_cxt; caller should reset that after use.
4244 : : */
4245 : : static const char **
4246 : 1052 : convert_prep_stmt_params(PgFdwModifyState *fmstate,
4247 : : ItemPointer tupleid,
4248 : : TupleTableSlot **slots,
4249 : : int numSlots)
4250 : : {
4251 : : const char **p_values;
4252 : : int i;
4253 : : int j;
4254 : 1052 : int pindex = 0;
4255 : : MemoryContext oldcontext;
4256 : :
4257 : 1052 : oldcontext = MemoryContextSwitchTo(fmstate->temp_cxt);
4258 : :
1690 tomas.vondra@postgre 4259 : 1052 : p_values = (const char **) palloc(sizeof(char *) * fmstate->p_nums * numSlots);
4260 : :
4261 : : /* ctid is provided only for UPDATE/DELETE, which don't allow batching */
4262 [ + + - + ]: 1052 : Assert(!(tupleid != NULL && numSlots > 1));
4263 : :
4264 : : /* 1st parameter should be ctid, if it's in use */
4563 tgl@sss.pgh.pa.us 4265 [ + + ]: 1052 : if (tupleid != NULL)
4266 : : {
1690 tomas.vondra@postgre 4267 [ - + ]: 118 : Assert(numSlots == 1);
4268 : : /* don't need set_transmission_modes for TID output */
4563 tgl@sss.pgh.pa.us 4269 : 118 : p_values[pindex] = OutputFunctionCall(&fmstate->p_flinfo[pindex],
4270 : : PointerGetDatum(tupleid));
4271 : 118 : pindex++;
4272 : : }
4273 : :
4274 : : /* get following parameters from slots */
1690 tomas.vondra@postgre 4275 [ + - + + ]: 1052 : if (slots != NULL && fmstate->target_attrs != NIL)
4276 : : {
1493 efujita@postgresql.o 4277 : 1026 : TupleDesc tupdesc = RelationGetDescr(fmstate->rel);
4278 : : int nestlevel;
4279 : : ListCell *lc;
4280 : :
4562 tgl@sss.pgh.pa.us 4281 : 1026 : nestlevel = set_transmission_modes();
4282 : :
1690 tomas.vondra@postgre 4283 [ + + ]: 2174 : for (i = 0; i < numSlots; i++)
4284 : : {
4285 : 1148 : j = (tupleid != NULL) ? 1 : 0;
4286 [ + - + + : 4797 : foreach(lc, fmstate->target_attrs)
+ + ]
4287 : : {
4288 : 3649 : int attnum = lfirst_int(lc);
260 drowley@postgresql.o 4289 : 3649 : CompactAttribute *attr = TupleDescCompactAttr(tupdesc, attnum - 1);
4290 : : Datum value;
4291 : : bool isnull;
4292 : :
4293 : : /* Ignore generated columns; they are set to DEFAULT */
1493 efujita@postgresql.o 4294 [ + + ]: 3649 : if (attr->attgenerated)
4295 : 14 : continue;
1690 tomas.vondra@postgre 4296 : 3635 : value = slot_getattr(slots[i], attnum, &isnull);
4297 [ + + ]: 3635 : if (isnull)
4298 : 583 : p_values[pindex] = NULL;
4299 : : else
4300 : 3052 : p_values[pindex] = OutputFunctionCall(&fmstate->p_flinfo[j],
4301 : : value);
4302 : 3635 : pindex++;
4303 : 3635 : j++;
4304 : : }
4305 : : }
4306 : :
4562 tgl@sss.pgh.pa.us 4307 : 1026 : reset_transmission_modes(nestlevel);
4308 : : }
4309 : :
1690 tomas.vondra@postgre 4310 [ - + ]: 1052 : Assert(pindex == fmstate->p_nums * numSlots);
4311 : :
4563 tgl@sss.pgh.pa.us 4312 : 1052 : MemoryContextSwitchTo(oldcontext);
4313 : :
4314 : 1052 : return p_values;
4315 : : }
4316 : :
4317 : : /*
4318 : : * store_returning_result
4319 : : * Store the result of a RETURNING clause
4320 : : */
4321 : : static void
4322 : 107 : store_returning_result(PgFdwModifyState *fmstate,
4323 : : TupleTableSlot *slot, PGresult *res)
4324 : : {
4325 : : HeapTuple newtup;
4326 : :
43 tgl@sss.pgh.pa.us 4327 :GNC 107 : newtup = make_tuple_from_result_row(res, 0,
4328 : : fmstate->rel,
4329 : : fmstate->attinmeta,
4330 : : fmstate->retrieved_attrs,
4331 : : NULL,
4332 : : fmstate->temp_cxt);
4333 : :
4334 : : /*
4335 : : * The returning slot will not necessarily be suitable to store heaptuples
4336 : : * directly, so allow for conversion.
4337 : : */
4338 : 107 : ExecForceStoreHeapTuple(newtup, slot, true);
4563 tgl@sss.pgh.pa.us 4339 :CBC 107 : }
4340 : :
4341 : : /*
4342 : : * finish_foreign_modify
4343 : : * Release resources for a foreign insert/update/delete operation
4344 : : */
4345 : : static void
2710 rhaas@postgresql.org 4346 : 160 : finish_foreign_modify(PgFdwModifyState *fmstate)
4347 : : {
4348 [ - + ]: 160 : Assert(fmstate != NULL);
4349 : :
4350 : : /* If we created a prepared statement, destroy it */
1690 tomas.vondra@postgre 4351 : 160 : deallocate_query(fmstate);
4352 : :
4353 : : /* Release remote connection */
2710 rhaas@postgresql.org 4354 : 160 : ReleaseConnection(fmstate->conn);
4355 : 160 : fmstate->conn = NULL;
4356 : 160 : }
4357 : :
4358 : : /*
4359 : : * deallocate_query
4360 : : * Deallocate a prepared statement for a foreign insert/update/delete
4361 : : * operation
4362 : : */
4363 : : static void
1690 tomas.vondra@postgre 4364 : 171 : deallocate_query(PgFdwModifyState *fmstate)
4365 : : {
4366 : : char sql[64];
4367 : : PGresult *res;
4368 : :
4369 : : /* do nothing if the query is not allocated */
4370 [ + + ]: 171 : if (!fmstate->p_name)
4371 : 4 : return;
4372 : :
4373 : 167 : snprintf(sql, sizeof(sql), "DEALLOCATE %s", fmstate->p_name);
1620 efujita@postgresql.o 4374 : 167 : res = pgfdw_exec_query(fmstate->conn, sql, fmstate->conn_state);
1690 tomas.vondra@postgre 4375 [ - + ]: 167 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 4376 :UNC 0 : pgfdw_report_error(res, fmstate->conn, sql);
1690 tomas.vondra@postgre 4377 :CBC 167 : PQclear(res);
1684 michael@paquier.xyz 4378 : 167 : pfree(fmstate->p_name);
1690 tomas.vondra@postgre 4379 : 167 : fmstate->p_name = NULL;
4380 : : }
4381 : :
4382 : : /*
4383 : : * build_remote_returning
4384 : : * Build a RETURNING targetlist of a remote query for performing an
4385 : : * UPDATE/DELETE .. RETURNING on a join directly
4386 : : */
4387 : : static List *
2768 rhaas@postgresql.org 4388 : 4 : build_remote_returning(Index rtindex, Relation rel, List *returningList)
4389 : : {
4390 : 4 : bool have_wholerow = false;
4391 : 4 : List *tlist = NIL;
4392 : : List *vars;
4393 : : ListCell *lc;
4394 : :
4395 [ - + ]: 4 : Assert(returningList);
4396 : :
4397 : 4 : vars = pull_var_clause((Node *) returningList, PVC_INCLUDE_PLACEHOLDERS);
4398 : :
4399 : : /*
4400 : : * If there's a whole-row reference to the target relation, then we'll
4401 : : * need all the columns of the relation.
4402 : : */
4403 [ + + + - : 4 : foreach(lc, vars)
+ + ]
4404 : : {
4405 : 2 : Var *var = (Var *) lfirst(lc);
4406 : :
4407 [ + - ]: 2 : if (IsA(var, Var) &&
4408 [ + - ]: 2 : var->varno == rtindex &&
4409 [ + - ]: 2 : var->varattno == InvalidAttrNumber)
4410 : : {
4411 : 2 : have_wholerow = true;
4412 : 2 : break;
4413 : : }
4414 : : }
4415 : :
4416 [ + + ]: 4 : if (have_wholerow)
4417 : : {
4418 : 2 : TupleDesc tupdesc = RelationGetDescr(rel);
4419 : : int i;
4420 : :
4421 [ + + ]: 20 : for (i = 1; i <= tupdesc->natts; i++)
4422 : : {
4423 : 18 : Form_pg_attribute attr = TupleDescAttr(tupdesc, i - 1);
4424 : : Var *var;
4425 : :
4426 : : /* Ignore dropped attributes. */
4427 [ + + ]: 18 : if (attr->attisdropped)
4428 : 2 : continue;
4429 : :
4430 : 16 : var = makeVar(rtindex,
4431 : : i,
4432 : : attr->atttypid,
4433 : : attr->atttypmod,
4434 : : attr->attcollation,
4435 : : 0);
4436 : :
4437 : 16 : tlist = lappend(tlist,
4438 : 16 : makeTargetEntry((Expr *) var,
4439 : 16 : list_length(tlist) + 1,
4440 : : NULL,
4441 : : false));
4442 : : }
4443 : : }
4444 : :
4445 : : /* Now add any remaining columns to tlist. */
4446 [ + + + + : 30 : foreach(lc, vars)
+ + ]
4447 : : {
4448 : 26 : Var *var = (Var *) lfirst(lc);
4449 : :
4450 : : /*
4451 : : * No need for whole-row references to the target relation. We don't
4452 : : * need system columns other than ctid and oid either, since those are
4453 : : * set locally.
4454 : : */
4455 [ + - ]: 26 : if (IsA(var, Var) &&
4456 [ + + ]: 26 : var->varno == rtindex &&
4457 [ + + ]: 18 : var->varattno <= InvalidAttrNumber &&
2482 andres@anarazel.de 4458 [ + - ]: 2 : var->varattno != SelfItemPointerAttributeNumber)
2768 rhaas@postgresql.org 4459 : 2 : continue; /* don't need it */
4460 : :
4461 [ + + ]: 24 : if (tlist_member((Expr *) var, tlist))
4462 : 16 : continue; /* already got it */
4463 : :
4464 : 8 : tlist = lappend(tlist,
4465 : 8 : makeTargetEntry((Expr *) var,
4466 : 8 : list_length(tlist) + 1,
4467 : : NULL,
4468 : : false));
4469 : : }
4470 : :
4471 : 4 : list_free(vars);
4472 : :
4473 : 4 : return tlist;
4474 : : }
4475 : :
4476 : : /*
4477 : : * rebuild_fdw_scan_tlist
4478 : : * Build new fdw_scan_tlist of given foreign-scan plan node from given
4479 : : * tlist
4480 : : *
4481 : : * There might be columns that the fdw_scan_tlist of the given foreign-scan
4482 : : * plan node contains that the given tlist doesn't. The fdw_scan_tlist would
4483 : : * have contained resjunk columns such as 'ctid' of the target relation and
4484 : : * 'wholerow' of non-target relations, but the tlist might not contain them,
4485 : : * for example. So, adjust the tlist so it contains all the columns specified
4486 : : * in the fdw_scan_tlist; else setrefs.c will get confused.
4487 : : */
4488 : : static void
4489 : 2 : rebuild_fdw_scan_tlist(ForeignScan *fscan, List *tlist)
4490 : : {
4491 : 2 : List *new_tlist = tlist;
4492 : 2 : List *old_tlist = fscan->fdw_scan_tlist;
4493 : : ListCell *lc;
4494 : :
4495 [ + - + + : 16 : foreach(lc, old_tlist)
+ + ]
4496 : : {
4497 : 14 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
4498 : :
4499 [ + + ]: 14 : if (tlist_member(tle->expr, new_tlist))
4500 : 8 : continue; /* already got it */
4501 : :
4502 : 6 : new_tlist = lappend(new_tlist,
4503 : 6 : makeTargetEntry(tle->expr,
4504 : 6 : list_length(new_tlist) + 1,
4505 : : NULL,
4506 : : false));
4507 : : }
4508 : 2 : fscan->fdw_scan_tlist = new_tlist;
4509 : 2 : }
4510 : :
4511 : : /*
4512 : : * Execute a direct UPDATE/DELETE statement.
4513 : : */
4514 : : static void
3459 4515 : 71 : execute_dml_stmt(ForeignScanState *node)
4516 : : {
4517 : 71 : PgFdwDirectModifyState *dmstate = (PgFdwDirectModifyState *) node->fdw_state;
4518 : 71 : ExprContext *econtext = node->ss.ps.ps_ExprContext;
4519 : 71 : int numParams = dmstate->numParams;
4520 : 71 : const char **values = dmstate->param_values;
4521 : :
4522 : : /* First, process a pending asynchronous request, if any. */
1620 efujita@postgresql.o 4523 [ + + ]: 71 : if (dmstate->conn_state->pendingAreq)
4524 : 1 : process_pending_request(dmstate->conn_state->pendingAreq);
4525 : :
4526 : : /*
4527 : : * Construct array of query parameter values in text format.
4528 : : */
3459 rhaas@postgresql.org 4529 [ - + ]: 71 : if (numParams > 0)
3459 rhaas@postgresql.org 4530 :UBC 0 : process_query_params(econtext,
4531 : : dmstate->param_flinfo,
4532 : : dmstate->param_exprs,
4533 : : values);
4534 : :
4535 : : /*
4536 : : * Notice that we pass NULL for paramTypes, thus forcing the remote server
4537 : : * to infer types for all parameters. Since we explicitly cast every
4538 : : * parameter (see deparse.c), the "inference" is trivial and will produce
4539 : : * the desired result. This allows us to avoid assuming that the remote
4540 : : * server has the same OIDs we do for the parameters' types.
4541 : : */
3425 rhaas@postgresql.org 4542 [ - + ]:CBC 71 : if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams,
4543 : : NULL, values, NULL, NULL, 0))
39 tgl@sss.pgh.pa.us 4544 :UNC 0 : pgfdw_report_error(NULL, dmstate->conn, dmstate->query);
4545 : :
4546 : : /*
4547 : : * Get the result, and check for success.
4548 : : */
607 noah@leadboat.com 4549 :CBC 71 : dmstate->result = pgfdw_get_result(dmstate->conn);
3459 rhaas@postgresql.org 4550 [ + + ]: 142 : if (PQresultStatus(dmstate->result) !=
4551 [ + + ]: 71 : (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
39 tgl@sss.pgh.pa.us 4552 :GNC 4 : pgfdw_report_error(dmstate->result, dmstate->conn,
3459 rhaas@postgresql.org 4553 :CBC 4 : dmstate->query);
4554 : :
4555 : : /*
4556 : : * The result potentially needs to survive across multiple executor row
4557 : : * cycles, so move it to the context where the dmstate is.
4558 : : */
43 tgl@sss.pgh.pa.us 4559 :GNC 67 : dmstate->result = libpqsrv_PGresultSetParent(dmstate->result,
4560 : : GetMemoryChunkContext(dmstate));
4561 : :
4562 : : /* Get the number of rows affected. */
3459 rhaas@postgresql.org 4563 [ + + ]:CBC 67 : if (dmstate->has_returning)
4564 : 14 : dmstate->num_tuples = PQntuples(dmstate->result);
4565 : : else
4566 : 53 : dmstate->num_tuples = atoi(PQcmdTuples(dmstate->result));
4567 : 67 : }
4568 : :
4569 : : /*
4570 : : * Get the result of a RETURNING clause.
4571 : : */
4572 : : static TupleTableSlot *
4573 : 364 : get_returning_data(ForeignScanState *node)
4574 : : {
4575 : 364 : PgFdwDirectModifyState *dmstate = (PgFdwDirectModifyState *) node->fdw_state;
4576 : 364 : EState *estate = node->ss.ps.state;
1788 heikki.linnakangas@i 4577 : 364 : ResultRelInfo *resultRelInfo = node->resultRelInfo;
3459 rhaas@postgresql.org 4578 : 364 : TupleTableSlot *slot = node->ss.ss_ScanTupleSlot;
4579 : : TupleTableSlot *resultSlot;
4580 : :
4581 [ - + ]: 364 : Assert(resultRelInfo->ri_projectReturning);
4582 : :
4583 : : /* If we didn't get any tuples, must be end of data. */
4584 [ + + ]: 364 : if (dmstate->next_tuple >= dmstate->num_tuples)
4585 : 17 : return ExecClearTuple(slot);
4586 : :
4587 : : /* Increment the command es_processed count if necessary. */
4588 [ + + ]: 347 : if (dmstate->set_processed)
4589 : 346 : estate->es_processed += 1;
4590 : :
4591 : : /*
4592 : : * Store a RETURNING tuple. If has_returning is false, just emit a dummy
4593 : : * tuple. (has_returning is false when the local query is of the form
4594 : : * "UPDATE/DELETE .. RETURNING 1" for example.)
4595 : : */
4596 [ + + ]: 347 : if (!dmstate->has_returning)
4597 : : {
4598 : 12 : ExecStoreAllNullTuple(slot);
2768 4599 : 12 : resultSlot = slot;
4600 : : }
4601 : : else
4602 : : {
4603 : : HeapTuple newtup;
4604 : :
99 tgl@sss.pgh.pa.us 4605 : 335 : newtup = make_tuple_from_result_row(dmstate->result,
4606 : : dmstate->next_tuple,
4607 : : dmstate->rel,
4608 : : dmstate->attinmeta,
4609 : : dmstate->retrieved_attrs,
4610 : : node,
4611 : : dmstate->temp_cxt);
4612 : 335 : ExecStoreHeapTuple(newtup, slot, false);
4613 : : /* Get the updated/deleted tuple. */
2768 rhaas@postgresql.org 4614 [ + + ]: 335 : if (dmstate->rel)
4615 : 319 : resultSlot = slot;
4616 : : else
1788 heikki.linnakangas@i 4617 : 16 : resultSlot = apply_returning_filter(dmstate, resultRelInfo, slot, estate);
4618 : : }
3459 rhaas@postgresql.org 4619 : 347 : dmstate->next_tuple++;
4620 : :
4621 : : /* Make slot available for evaluation of the local query RETURNING list. */
2768 4622 : 347 : resultRelInfo->ri_projectReturning->pi_exprContext->ecxt_scantuple =
4623 : : resultSlot;
4624 : :
3459 4625 : 347 : return slot;
4626 : : }
4627 : :
4628 : : /*
4629 : : * Initialize a filter to extract an updated/deleted tuple from a scan tuple.
4630 : : */
4631 : : static void
2768 4632 : 1 : init_returning_filter(PgFdwDirectModifyState *dmstate,
4633 : : List *fdw_scan_tlist,
4634 : : Index rtindex)
4635 : : {
4636 : 1 : TupleDesc resultTupType = RelationGetDescr(dmstate->resultRel);
4637 : : ListCell *lc;
4638 : : int i;
4639 : :
4640 : : /*
4641 : : * Calculate the mapping between the fdw_scan_tlist's entries and the
4642 : : * result tuple's attributes.
4643 : : *
4644 : : * The "map" is an array of indexes of the result tuple's attributes in
4645 : : * fdw_scan_tlist, i.e., one entry for every attribute of the result
4646 : : * tuple. We store zero for any attributes that don't have the
4647 : : * corresponding entries in that list, marking that a NULL is needed in
4648 : : * the result tuple.
4649 : : *
4650 : : * Also get the indexes of the entries for ctid and oid if any.
4651 : : */
4652 : 1 : dmstate->attnoMap = (AttrNumber *)
4653 : 1 : palloc0(resultTupType->natts * sizeof(AttrNumber));
4654 : :
4655 : 1 : dmstate->ctidAttno = dmstate->oidAttno = 0;
4656 : :
4657 : 1 : i = 1;
4658 : 1 : dmstate->hasSystemCols = false;
4659 [ + - + + : 16 : foreach(lc, fdw_scan_tlist)
+ + ]
4660 : : {
4661 : 15 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
4662 : 15 : Var *var = (Var *) tle->expr;
4663 : :
4664 [ - + ]: 15 : Assert(IsA(var, Var));
4665 : :
4666 : : /*
4667 : : * If the Var is a column of the target relation to be retrieved from
4668 : : * the foreign server, get the index of the entry.
4669 : : */
4670 [ + + + + ]: 25 : if (var->varno == rtindex &&
4671 : 10 : list_member_int(dmstate->retrieved_attrs, i))
4672 : : {
4673 : 8 : int attrno = var->varattno;
4674 : :
4675 [ - + ]: 8 : if (attrno < 0)
4676 : : {
4677 : : /*
4678 : : * We don't retrieve system columns other than ctid and oid.
4679 : : */
2768 rhaas@postgresql.org 4680 [ # # ]:UBC 0 : if (attrno == SelfItemPointerAttributeNumber)
4681 : 0 : dmstate->ctidAttno = i;
4682 : : else
4683 : 0 : Assert(false);
4684 : 0 : dmstate->hasSystemCols = true;
4685 : : }
4686 : : else
4687 : : {
4688 : : /*
4689 : : * We don't retrieve whole-row references to the target
4690 : : * relation either.
4691 : : */
2768 rhaas@postgresql.org 4692 [ - + ]:CBC 8 : Assert(attrno > 0);
4693 : :
4694 : 8 : dmstate->attnoMap[attrno - 1] = i;
4695 : : }
4696 : : }
4697 : 15 : i++;
4698 : : }
4699 : 1 : }
4700 : :
4701 : : /*
4702 : : * Extract and return an updated/deleted tuple from a scan tuple.
4703 : : */
4704 : : static TupleTableSlot *
4705 : 16 : apply_returning_filter(PgFdwDirectModifyState *dmstate,
4706 : : ResultRelInfo *resultRelInfo,
4707 : : TupleTableSlot *slot,
4708 : : EState *estate)
4709 : : {
4710 : 16 : TupleDesc resultTupType = RelationGetDescr(dmstate->resultRel);
4711 : : TupleTableSlot *resultSlot;
4712 : : Datum *values;
4713 : : bool *isnull;
4714 : : Datum *old_values;
4715 : : bool *old_isnull;
4716 : : int i;
4717 : :
4718 : : /*
4719 : : * Use the return tuple slot as a place to store the result tuple.
4720 : : */
1788 heikki.linnakangas@i 4721 : 16 : resultSlot = ExecGetReturningSlot(estate, resultRelInfo);
4722 : :
4723 : : /*
4724 : : * Extract all the values of the scan tuple.
4725 : : */
2768 rhaas@postgresql.org 4726 : 16 : slot_getallattrs(slot);
4727 : 16 : old_values = slot->tts_values;
4728 : 16 : old_isnull = slot->tts_isnull;
4729 : :
4730 : : /*
4731 : : * Prepare to build the result tuple.
4732 : : */
4733 : 16 : ExecClearTuple(resultSlot);
4734 : 16 : values = resultSlot->tts_values;
4735 : 16 : isnull = resultSlot->tts_isnull;
4736 : :
4737 : : /*
4738 : : * Transpose data into proper fields of the result tuple.
4739 : : */
4740 [ + + ]: 160 : for (i = 0; i < resultTupType->natts; i++)
4741 : : {
4742 : 144 : int j = dmstate->attnoMap[i];
4743 : :
4744 [ + + ]: 144 : if (j == 0)
4745 : : {
4746 : 16 : values[i] = (Datum) 0;
4747 : 16 : isnull[i] = true;
4748 : : }
4749 : : else
4750 : : {
4751 : 128 : values[i] = old_values[j - 1];
4752 : 128 : isnull[i] = old_isnull[j - 1];
4753 : : }
4754 : : }
4755 : :
4756 : : /*
4757 : : * Build the virtual tuple.
4758 : : */
4759 : 16 : ExecStoreVirtualTuple(resultSlot);
4760 : :
4761 : : /*
4762 : : * If we have any system columns to return, materialize a heap tuple in
4763 : : * the slot from column values set above and install system columns in
4764 : : * that tuple.
4765 : : */
4766 [ - + ]: 16 : if (dmstate->hasSystemCols)
4767 : : {
2487 andres@anarazel.de 4768 :UBC 0 : HeapTuple resultTup = ExecFetchSlotHeapTuple(resultSlot, true, NULL);
4769 : :
4770 : : /* ctid */
2768 rhaas@postgresql.org 4771 [ # # ]: 0 : if (dmstate->ctidAttno)
4772 : : {
4773 : 0 : ItemPointer ctid = NULL;
4774 : :
4775 : 0 : ctid = (ItemPointer) DatumGetPointer(old_values[dmstate->ctidAttno - 1]);
4776 : 0 : resultTup->t_self = *ctid;
4777 : : }
4778 : :
4779 : : /*
4780 : : * And remaining columns
4781 : : *
4782 : : * Note: since we currently don't allow the target relation to appear
4783 : : * on the nullable side of an outer join, any system columns wouldn't
4784 : : * go to NULL.
4785 : : *
4786 : : * Note: no need to care about tableoid here because it will be
4787 : : * initialized in ExecProcessReturning().
4788 : : */
4789 : 0 : HeapTupleHeaderSetXmin(resultTup->t_data, InvalidTransactionId);
4790 : 0 : HeapTupleHeaderSetXmax(resultTup->t_data, InvalidTransactionId);
4791 : 0 : HeapTupleHeaderSetCmin(resultTup->t_data, InvalidTransactionId);
4792 : : }
4793 : :
4794 : : /*
4795 : : * And return the result tuple.
4796 : : */
2768 rhaas@postgresql.org 4797 :CBC 16 : return resultSlot;
4798 : : }
4799 : :
4800 : : /*
4801 : : * Prepare for processing of parameters used in remote query.
4802 : : */
4803 : : static void
3459 4804 : 19 : prepare_query_params(PlanState *node,
4805 : : List *fdw_exprs,
4806 : : int numParams,
4807 : : FmgrInfo **param_flinfo,
4808 : : List **param_exprs,
4809 : : const char ***param_values)
4810 : : {
4811 : : int i;
4812 : : ListCell *lc;
4813 : :
4814 [ - + ]: 19 : Assert(numParams > 0);
4815 : :
4816 : : /* Prepare for output conversion of parameters used in remote query. */
4817 : 19 : *param_flinfo = (FmgrInfo *) palloc0(sizeof(FmgrInfo) * numParams);
4818 : :
4819 : 19 : i = 0;
4820 [ + - + + : 39 : foreach(lc, fdw_exprs)
+ + ]
4821 : : {
4822 : 20 : Node *param_expr = (Node *) lfirst(lc);
4823 : : Oid typefnoid;
4824 : : bool isvarlena;
4825 : :
4826 : 20 : getTypeOutputInfo(exprType(param_expr), &typefnoid, &isvarlena);
4827 : 20 : fmgr_info(typefnoid, &(*param_flinfo)[i]);
4828 : 20 : i++;
4829 : : }
4830 : :
4831 : : /*
4832 : : * Prepare remote-parameter expressions for evaluation. (Note: in
4833 : : * practice, we expect that all these expressions will be just Params, so
4834 : : * we could possibly do something more efficient than using the full
4835 : : * expression-eval machinery for this. But probably there would be little
4836 : : * benefit, and it'd require postgres_fdw to know more than is desirable
4837 : : * about Param evaluation.)
4838 : : */
3098 andres@anarazel.de 4839 : 19 : *param_exprs = ExecInitExprList(fdw_exprs, node);
4840 : :
4841 : : /* Allocate buffer for text form of query parameters. */
3459 rhaas@postgresql.org 4842 : 19 : *param_values = (const char **) palloc0(numParams * sizeof(char *));
4843 : 19 : }
4844 : :
4845 : : /*
4846 : : * Construct array of query parameter values in text format.
4847 : : */
4848 : : static void
4849 : 347 : process_query_params(ExprContext *econtext,
4850 : : FmgrInfo *param_flinfo,
4851 : : List *param_exprs,
4852 : : const char **param_values)
4853 : : {
4854 : : int nestlevel;
4855 : : int i;
4856 : : ListCell *lc;
4857 : :
4858 : 347 : nestlevel = set_transmission_modes();
4859 : :
4860 : 347 : i = 0;
4861 [ + - + + : 894 : foreach(lc, param_exprs)
+ + ]
4862 : : {
4863 : 547 : ExprState *expr_state = (ExprState *) lfirst(lc);
4864 : : Datum expr_value;
4865 : : bool isNull;
4866 : :
4867 : : /* Evaluate the parameter expression */
3152 andres@anarazel.de 4868 : 547 : expr_value = ExecEvalExpr(expr_state, econtext, &isNull);
4869 : :
4870 : : /*
4871 : : * Get string representation of each parameter value by invoking
4872 : : * type-specific output function, unless the value is null.
4873 : : */
3459 rhaas@postgresql.org 4874 [ - + ]: 547 : if (isNull)
3459 rhaas@postgresql.org 4875 :UBC 0 : param_values[i] = NULL;
4876 : : else
3459 rhaas@postgresql.org 4877 :CBC 547 : param_values[i] = OutputFunctionCall(¶m_flinfo[i], expr_value);
4878 : :
3456 tgl@sss.pgh.pa.us 4879 : 547 : i++;
4880 : : }
4881 : :
3459 rhaas@postgresql.org 4882 : 347 : reset_transmission_modes(nestlevel);
4883 : 347 : }
4884 : :
4885 : : /*
4886 : : * postgresAnalyzeForeignTable
4887 : : * Test whether analyzing this foreign table is supported
4888 : : */
4889 : : static bool
4580 tgl@sss.pgh.pa.us 4890 : 47 : postgresAnalyzeForeignTable(Relation relation,
4891 : : AcquireSampleRowsFunc *func,
4892 : : BlockNumber *totalpages)
4893 : : {
4894 : : ForeignTable *table;
4895 : : UserMapping *user;
4896 : : PGconn *conn;
4897 : : StringInfoData sql;
4898 : : PGresult *res;
4899 : :
4900 : : /* Return the row-analysis function pointer */
4901 : 47 : *func = postgresAcquireSampleRowsFunc;
4902 : :
4903 : : /*
4904 : : * Now we have to get the number of pages. It's annoying that the ANALYZE
4905 : : * API requires us to return that now, because it forces some duplication
4906 : : * of effort between this routine and postgresAcquireSampleRowsFunc. But
4907 : : * it's probably not worth redefining that API at this point.
4908 : : */
4909 : :
4910 : : /*
4911 : : * Get the connection to use. We do the remote access as the table's
4912 : : * owner, even if the ANALYZE was started by some other user.
4913 : : */
4579 4914 : 47 : table = GetForeignTable(RelationGetRelid(relation));
3509 rhaas@postgresql.org 4915 : 47 : user = GetUserMapping(relation->rd_rel->relowner, table->serverid);
1620 efujita@postgresql.o 4916 : 47 : conn = GetConnection(user, false, NULL);
4917 : :
4918 : : /*
4919 : : * Construct command to get page count for relation.
4920 : : */
4579 tgl@sss.pgh.pa.us 4921 : 47 : initStringInfo(&sql);
4922 : 47 : deparseAnalyzeSizeSql(&sql, relation);
4923 : :
43 tgl@sss.pgh.pa.us 4924 :GNC 47 : res = pgfdw_exec_query(conn, sql.data, NULL);
4925 [ - + ]: 47 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 4926 :UNC 0 : pgfdw_report_error(res, conn, sql.data);
4927 : :
43 tgl@sss.pgh.pa.us 4928 [ + - - + ]:GNC 47 : if (PQntuples(res) != 1 || PQnfields(res) != 1)
43 tgl@sss.pgh.pa.us 4929 [ # # ]:UNC 0 : elog(ERROR, "unexpected result from deparseAnalyzeSizeSql query");
43 tgl@sss.pgh.pa.us 4930 :GNC 47 : *totalpages = strtoul(PQgetvalue(res, 0, 0), NULL, 10);
4931 : 47 : PQclear(res);
4932 : :
4579 tgl@sss.pgh.pa.us 4933 :CBC 47 : ReleaseConnection(conn);
4934 : :
4580 4935 : 47 : return true;
4936 : : }
4937 : :
4938 : : /*
4939 : : * postgresGetAnalyzeInfoForForeignTable
4940 : : * Count tuples in foreign table (just get pg_class.reltuples).
4941 : : *
4942 : : * can_tablesample determines if the remote relation supports acquiring the
4943 : : * sample using TABLESAMPLE.
4944 : : */
4945 : : static double
973 tomas.vondra@postgre 4946 : 46 : postgresGetAnalyzeInfoForForeignTable(Relation relation, bool *can_tablesample)
4947 : : {
4948 : : ForeignTable *table;
4949 : : UserMapping *user;
4950 : : PGconn *conn;
4951 : : StringInfoData sql;
4952 : : PGresult *res;
4953 : : double reltuples;
4954 : : char relkind;
4955 : :
4956 : : /* assume the remote relation does not support TABLESAMPLE */
4957 : 46 : *can_tablesample = false;
4958 : :
4959 : : /*
4960 : : * Get the connection to use. We do the remote access as the table's
4961 : : * owner, even if the ANALYZE was started by some other user.
4962 : : */
981 4963 : 46 : table = GetForeignTable(RelationGetRelid(relation));
4964 : 46 : user = GetUserMapping(relation->rd_rel->relowner, table->serverid);
4965 : 46 : conn = GetConnection(user, false, NULL);
4966 : :
4967 : : /*
4968 : : * Construct command to get page count for relation.
4969 : : */
4970 : 46 : initStringInfo(&sql);
973 4971 : 46 : deparseAnalyzeInfoSql(&sql, relation);
4972 : :
43 tgl@sss.pgh.pa.us 4973 :GNC 46 : res = pgfdw_exec_query(conn, sql.data, NULL);
4974 [ - + ]: 46 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 4975 :UNC 0 : pgfdw_report_error(res, conn, sql.data);
4976 : :
43 tgl@sss.pgh.pa.us 4977 [ + - - + ]:GNC 46 : if (PQntuples(res) != 1 || PQnfields(res) != 2)
43 tgl@sss.pgh.pa.us 4978 [ # # ]:UNC 0 : elog(ERROR, "unexpected result from deparseAnalyzeInfoSql query");
43 tgl@sss.pgh.pa.us 4979 :GNC 46 : reltuples = strtod(PQgetvalue(res, 0, 0), NULL);
4980 : 46 : relkind = *(PQgetvalue(res, 0, 1));
4981 : 46 : PQclear(res);
4982 : :
981 tomas.vondra@postgre 4983 :CBC 46 : ReleaseConnection(conn);
4984 : :
4985 : : /* TABLESAMPLE is supported only for regular tables and matviews */
973 tomas.vondra@postgre 4986 [ # # ]:LBC (92) : *can_tablesample = (relkind == RELKIND_RELATION ||
973 tomas.vondra@postgre 4987 [ - + - - ]:CBC 46 : relkind == RELKIND_MATVIEW ||
973 tomas.vondra@postgre 4988 [ # # ]:EUB : relkind == RELKIND_PARTITIONED_TABLE);
4989 : :
981 tomas.vondra@postgre 4990 :CBC 46 : return reltuples;
4991 : : }
4992 : :
4993 : : /*
4994 : : * Acquire a random sample of rows from foreign table managed by postgres_fdw.
4995 : : *
4996 : : * Selected rows are returned in the caller-allocated array rows[],
4997 : : * which must have at least targrows entries.
4998 : : * The actual number of rows selected is returned as the function result.
4999 : : * We also count the total number of rows in the table and return it into
5000 : : * *totalrows. Note that *totaldeadrows is always set to 0.
5001 : : *
5002 : : * Note that the returned list of rows is not always in order by physical
5003 : : * position in the table. Therefore, correlation estimates derived later
5004 : : * may be meaningless, but it's OK because we don't use the estimates
5005 : : * currently (the planner only pays attention to correlation for indexscans).
5006 : : */
5007 : : static int
4580 tgl@sss.pgh.pa.us 5008 : 47 : postgresAcquireSampleRowsFunc(Relation relation, int elevel,
5009 : : HeapTuple *rows, int targrows,
5010 : : double *totalrows,
5011 : : double *totaldeadrows)
5012 : : {
5013 : : PgFdwAnalyzeState astate;
5014 : : ForeignTable *table;
5015 : : ForeignServer *server;
5016 : : UserMapping *user;
5017 : : PGconn *conn;
5018 : : int server_version_num;
981 tomas.vondra@postgre 5019 : 47 : PgFdwSamplingMethod method = ANALYZE_SAMPLE_AUTO; /* auto is default */
5020 : 47 : double sample_frac = -1.0;
39 tgl@sss.pgh.pa.us 5021 :GNC 47 : double reltuples = -1.0;
5022 : : unsigned int cursor_number;
5023 : : StringInfoData sql;
5024 : : PGresult *res;
5025 : : char fetch_sql[64];
5026 : : int fetch_size;
5027 : : ListCell *lc;
5028 : :
5029 : : /* Initialize workspace state */
4580 tgl@sss.pgh.pa.us 5030 :CBC 47 : astate.rel = relation;
5031 : 47 : astate.attinmeta = TupleDescGetAttInMetadata(RelationGetDescr(relation));
5032 : :
5033 : 47 : astate.rows = rows;
5034 : 47 : astate.targrows = targrows;
5035 : 47 : astate.numrows = 0;
5036 : 47 : astate.samplerows = 0;
5037 : 47 : astate.rowstoskip = -1; /* -1 means not set yet */
3767 simon@2ndQuadrant.co 5038 : 47 : reservoir_init_selection_state(&astate.rstate, targrows);
5039 : :
5040 : : /* Remember ANALYZE context, and create a per-tuple temp context */
4580 tgl@sss.pgh.pa.us 5041 : 47 : astate.anl_cxt = CurrentMemoryContext;
5042 : 47 : astate.temp_cxt = AllocSetContextCreate(CurrentMemoryContext,
5043 : : "postgres_fdw temporary data",
5044 : : ALLOCSET_SMALL_SIZES);
5045 : :
5046 : : /*
5047 : : * Get the connection to use. We do the remote access as the table's
5048 : : * owner, even if the ANALYZE was started by some other user.
5049 : : */
5050 : 47 : table = GetForeignTable(RelationGetRelid(relation));
3503 rhaas@postgresql.org 5051 : 47 : server = GetForeignServer(table->serverid);
3509 5052 : 47 : user = GetUserMapping(relation->rd_rel->relowner, table->serverid);
1620 efujita@postgresql.o 5053 : 47 : conn = GetConnection(user, false, NULL);
5054 : :
5055 : : /* We'll need server version, so fetch it now. */
981 tomas.vondra@postgre 5056 : 47 : server_version_num = PQserverVersion(conn);
5057 : :
5058 : : /*
5059 : : * What sampling method should we use?
5060 : : */
5061 [ + - + + : 214 : foreach(lc, server->options)
+ + ]
5062 : : {
5063 : 172 : DefElem *def = (DefElem *) lfirst(lc);
5064 : :
5065 [ + + ]: 172 : if (strcmp(def->defname, "analyze_sampling") == 0)
5066 : : {
5067 : 5 : char *value = defGetString(def);
5068 : :
5069 [ + + ]: 5 : if (strcmp(value, "off") == 0)
5070 : 1 : method = ANALYZE_SAMPLE_OFF;
5071 [ + + ]: 4 : else if (strcmp(value, "auto") == 0)
5072 : 1 : method = ANALYZE_SAMPLE_AUTO;
5073 [ + + ]: 3 : else if (strcmp(value, "random") == 0)
5074 : 1 : method = ANALYZE_SAMPLE_RANDOM;
5075 [ + + ]: 2 : else if (strcmp(value, "system") == 0)
5076 : 1 : method = ANALYZE_SAMPLE_SYSTEM;
5077 [ + - ]: 1 : else if (strcmp(value, "bernoulli") == 0)
5078 : 1 : method = ANALYZE_SAMPLE_BERNOULLI;
5079 : :
5080 : 5 : break;
5081 : : }
5082 : : }
5083 : :
5084 [ + - + + : 108 : foreach(lc, table->options)
+ + ]
5085 : : {
5086 : 61 : DefElem *def = (DefElem *) lfirst(lc);
5087 : :
5088 [ - + ]: 61 : if (strcmp(def->defname, "analyze_sampling") == 0)
5089 : : {
981 tomas.vondra@postgre 5090 :UBC 0 : char *value = defGetString(def);
5091 : :
5092 [ # # ]: 0 : if (strcmp(value, "off") == 0)
5093 : 0 : method = ANALYZE_SAMPLE_OFF;
5094 [ # # ]: 0 : else if (strcmp(value, "auto") == 0)
5095 : 0 : method = ANALYZE_SAMPLE_AUTO;
5096 [ # # ]: 0 : else if (strcmp(value, "random") == 0)
5097 : 0 : method = ANALYZE_SAMPLE_RANDOM;
5098 [ # # ]: 0 : else if (strcmp(value, "system") == 0)
5099 : 0 : method = ANALYZE_SAMPLE_SYSTEM;
5100 [ # # ]: 0 : else if (strcmp(value, "bernoulli") == 0)
5101 : 0 : method = ANALYZE_SAMPLE_BERNOULLI;
5102 : :
5103 : 0 : break;
5104 : : }
5105 : : }
5106 : :
5107 : : /*
5108 : : * Error-out if explicitly required one of the TABLESAMPLE methods, but
5109 : : * the server does not support it.
5110 : : */
981 tomas.vondra@postgre 5111 [ - + - - ]:CBC 47 : if ((server_version_num < 95000) &&
981 tomas.vondra@postgre 5112 [ # # ]:UBC 0 : (method == ANALYZE_SAMPLE_SYSTEM ||
5113 : : method == ANALYZE_SAMPLE_BERNOULLI))
5114 [ # # ]: 0 : ereport(ERROR,
5115 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
5116 : : errmsg("remote server does not support TABLESAMPLE feature")));
5117 : :
5118 : : /*
5119 : : * If we've decided to do remote sampling, calculate the sampling rate. We
5120 : : * need to get the number of tuples from the remote server, but skip that
5121 : : * network round-trip if not needed.
5122 : : */
981 tomas.vondra@postgre 5123 [ + + ]:CBC 47 : if (method != ANALYZE_SAMPLE_OFF)
5124 : : {
5125 : : bool can_tablesample;
5126 : :
973 5127 : 46 : reltuples = postgresGetAnalyzeInfoForForeignTable(relation,
5128 : : &can_tablesample);
5129 : :
5130 : : /*
5131 : : * Make sure we're not choosing TABLESAMPLE when the remote relation
5132 : : * does not support that. But only do this for "auto" - if the user
5133 : : * explicitly requested BERNOULLI/SYSTEM, it's better to fail.
5134 : : */
5135 [ - + - - ]: 46 : if (!can_tablesample && (method == ANALYZE_SAMPLE_AUTO))
973 tomas.vondra@postgre 5136 :UBC 0 : method = ANALYZE_SAMPLE_RANDOM;
5137 : :
5138 : : /*
5139 : : * Remote's reltuples could be 0 or -1 if the table has never been
5140 : : * vacuumed/analyzed. In that case, disable sampling after all.
5141 : : */
981 tomas.vondra@postgre 5142 [ + + + - ]:CBC 46 : if ((reltuples <= 0) || (targrows >= reltuples))
5143 : 46 : method = ANALYZE_SAMPLE_OFF;
5144 : : else
5145 : : {
5146 : : /*
5147 : : * All supported sampling methods require sampling rate, not
5148 : : * target rows directly, so we calculate that using the remote
5149 : : * reltuples value. That's imperfect, because it might be off a
5150 : : * good deal, but that's not something we can (or should) address
5151 : : * here.
5152 : : *
5153 : : * If reltuples is too low (i.e. when table grew), we'll end up
5154 : : * sampling more rows - but then we'll apply the local sampling,
5155 : : * so we get the expected sample size. This is the same outcome as
5156 : : * without remote sampling.
5157 : : *
5158 : : * If reltuples is too high (e.g. after bulk DELETE), we will end
5159 : : * up sampling too few rows.
5160 : : *
5161 : : * We can't really do much better here - we could try sampling a
5162 : : * bit more rows, but we don't know how off the reltuples value is
5163 : : * so how much is "a bit more"?
5164 : : *
5165 : : * Furthermore, the targrows value for partitions is determined
5166 : : * based on table size (relpages), which can be off in different
5167 : : * ways too. Adjusting the sampling rate here might make the issue
5168 : : * worse.
5169 : : */
981 tomas.vondra@postgre 5170 :UBC 0 : sample_frac = targrows / reltuples;
5171 : :
5172 : : /*
5173 : : * We should never get sampling rate outside the valid range
5174 : : * (between 0.0 and 1.0), because those cases should be covered by
5175 : : * the previous branch that sets ANALYZE_SAMPLE_OFF.
5176 : : */
974 5177 [ # # # # ]: 0 : Assert(sample_frac >= 0.0 && sample_frac <= 1.0);
5178 : : }
5179 : : }
5180 : :
5181 : : /*
5182 : : * For "auto" method, pick the one we believe is best. For servers with
5183 : : * TABLESAMPLE support we pick BERNOULLI, for old servers we fall-back to
5184 : : * random() to at least reduce network transfer.
5185 : : */
973 tomas.vondra@postgre 5186 [ - + ]:CBC 47 : if (method == ANALYZE_SAMPLE_AUTO)
5187 : : {
973 tomas.vondra@postgre 5188 [ # # ]:UBC 0 : if (server_version_num < 95000)
5189 : 0 : method = ANALYZE_SAMPLE_RANDOM;
5190 : : else
5191 : 0 : method = ANALYZE_SAMPLE_BERNOULLI;
5192 : : }
5193 : :
5194 : : /*
5195 : : * Construct cursor that retrieves whole rows from remote.
5196 : : */
4580 tgl@sss.pgh.pa.us 5197 :CBC 47 : cursor_number = GetCursorNumber(conn);
5198 : 47 : initStringInfo(&sql);
5199 : 47 : appendStringInfo(&sql, "DECLARE c%u CURSOR FOR ", cursor_number);
5200 : :
981 tomas.vondra@postgre 5201 : 47 : deparseAnalyzeSql(&sql, relation, method, sample_frac, &astate.retrieved_attrs);
5202 : :
43 tgl@sss.pgh.pa.us 5203 :GNC 47 : res = pgfdw_exec_query(conn, sql.data, NULL);
5204 [ - + ]: 47 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
39 tgl@sss.pgh.pa.us 5205 :UNC 0 : pgfdw_report_error(res, conn, sql.data);
43 tgl@sss.pgh.pa.us 5206 :GNC 47 : PQclear(res);
5207 : :
5208 : : /*
5209 : : * Determine the fetch size. The default is arbitrary, but shouldn't be
5210 : : * enormous.
5211 : : */
5212 : 47 : fetch_size = 100;
5213 [ + - + + : 219 : foreach(lc, server->options)
+ + ]
5214 : : {
5215 : 172 : DefElem *def = (DefElem *) lfirst(lc);
5216 : :
5217 [ - + ]: 172 : if (strcmp(def->defname, "fetch_size") == 0)
5218 : : {
43 tgl@sss.pgh.pa.us 5219 :UNC 0 : (void) parse_int(defGetString(def), &fetch_size, 0, NULL);
5220 : 0 : break;
5221 : : }
5222 : : }
43 tgl@sss.pgh.pa.us 5223 [ + - + + :GNC 108 : foreach(lc, table->options)
+ + ]
5224 : : {
5225 : 61 : DefElem *def = (DefElem *) lfirst(lc);
5226 : :
5227 [ - + ]: 61 : if (strcmp(def->defname, "fetch_size") == 0)
43 tgl@sss.pgh.pa.us 5228 :ECB (222) : {
43 tgl@sss.pgh.pa.us 5229 :UNC 0 : (void) parse_int(defGetString(def), &fetch_size, 0, NULL);
5230 : 0 : break;
5231 : : }
5232 : : }
5233 : :
5234 : : /* Construct command to fetch rows from remote. */
43 tgl@sss.pgh.pa.us 5235 :GNC 47 : snprintf(fetch_sql, sizeof(fetch_sql), "FETCH %d FROM c%u",
5236 : : fetch_size, cursor_number);
5237 : :
5238 : : /* Retrieve and process rows a batch at a time. */
5239 : : for (;;)
5240 : 222 : {
5241 : : int numrows;
5242 : : int i;
5243 : :
5244 : : /* Allow users to cancel long query */
5245 [ - + ]: 269 : CHECK_FOR_INTERRUPTS();
5246 : :
5247 : : /*
5248 : : * XXX possible future improvement: if rowstoskip is large, we could
5249 : : * issue a MOVE rather than physically fetching the rows, then just
5250 : : * adjust rowstoskip and samplerows appropriately.
5251 : : */
5252 : :
5253 : : /* Fetch some rows */
5254 : 269 : res = pgfdw_exec_query(conn, fetch_sql, NULL);
5255 : : /* On error, report the original query, not the FETCH. */
5256 [ - + ]: 269 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 5257 :UNC 0 : pgfdw_report_error(res, conn, sql.data);
5258 : :
5259 : : /* Process whatever we got. */
43 tgl@sss.pgh.pa.us 5260 :GNC 269 : numrows = PQntuples(res);
5261 [ + + ]: 22996 : for (i = 0; i < numrows; i++)
5262 : 22728 : analyze_row_processor(res, i, &astate);
5263 : :
43 tgl@sss.pgh.pa.us 5264 :CBC 268 : PQclear(res);
5265 : :
5266 : : /* Must be EOF if we didn't get all the rows requested. */
43 tgl@sss.pgh.pa.us 5267 [ + + ]:GNC 268 : if (numrows < fetch_size)
5268 : 46 : break;
5269 : : }
5270 : :
5271 : : /* Close the cursor, just to be tidy. */
5272 : 46 : close_cursor(conn, cursor_number, NULL);
5273 : :
4580 tgl@sss.pgh.pa.us 5274 :CBC 46 : ReleaseConnection(conn);
5275 : :
5276 : : /* We assume that we have no dead tuple. */
5277 : 46 : *totaldeadrows = 0.0;
5278 : :
5279 : : /*
5280 : : * Without sampling, we've retrieved all living tuples from foreign
5281 : : * server, so report that as totalrows. Otherwise use the reltuples
5282 : : * estimate we got from the remote side.
5283 : : */
981 tomas.vondra@postgre 5284 [ + - ]: 46 : if (method == ANALYZE_SAMPLE_OFF)
5285 : 46 : *totalrows = astate.samplerows;
5286 : : else
981 tomas.vondra@postgre 5287 :UBC 0 : *totalrows = reltuples;
5288 : :
5289 : : /*
5290 : : * Emit some interesting relation info
5291 : : */
4580 tgl@sss.pgh.pa.us 5292 [ - + ]:CBC 46 : ereport(elevel,
5293 : : (errmsg("\"%s\": table contains %.0f rows, %d rows in sample",
5294 : : RelationGetRelationName(relation),
5295 : : *totalrows, astate.numrows)));
5296 : :
5297 : 46 : return astate.numrows;
5298 : : }
5299 : :
5300 : : /*
5301 : : * Collect sample rows from the result of query.
5302 : : * - Use all tuples in sample until target # of samples are collected.
5303 : : * - Subsequently, replace already-sampled tuples randomly.
5304 : : */
5305 : : static void
5306 : 22728 : analyze_row_processor(PGresult *res, int row, PgFdwAnalyzeState *astate)
5307 : : {
5308 : 22728 : int targrows = astate->targrows;
5309 : : int pos; /* array index to store tuple in */
5310 : : MemoryContext oldcontext;
5311 : :
5312 : : /* Always increment sample row counter. */
5313 : 22728 : astate->samplerows += 1;
5314 : :
5315 : : /*
5316 : : * Determine the slot where this sample row should be stored. Set pos to
5317 : : * negative value to indicate the row should be skipped.
5318 : : */
5319 [ + - ]: 22728 : if (astate->numrows < targrows)
5320 : : {
5321 : : /* First targrows rows are always included into the sample */
5322 : 22728 : pos = astate->numrows++;
5323 : : }
5324 : : else
5325 : : {
5326 : : /*
5327 : : * Now we start replacing tuples in the sample until we reach the end
5328 : : * of the relation. Same algorithm as in acquire_sample_rows in
5329 : : * analyze.c; see Jeff Vitter's paper.
5330 : : */
4580 tgl@sss.pgh.pa.us 5331 [ # # ]:UBC 0 : if (astate->rowstoskip < 0)
3767 simon@2ndQuadrant.co 5332 : 0 : astate->rowstoskip = reservoir_get_next_S(&astate->rstate, astate->samplerows, targrows);
5333 : :
4580 tgl@sss.pgh.pa.us 5334 [ # # ]: 0 : if (astate->rowstoskip <= 0)
5335 : : {
5336 : : /* Choose a random reservoir element to replace. */
1378 5337 : 0 : pos = (int) (targrows * sampler_random_fract(&astate->rstate.randstate));
4580 5338 [ # # # # ]: 0 : Assert(pos >= 0 && pos < targrows);
5339 : 0 : heap_freetuple(astate->rows[pos]);
5340 : : }
5341 : : else
5342 : : {
5343 : : /* Skip this tuple. */
5344 : 0 : pos = -1;
5345 : : }
5346 : :
5347 : 0 : astate->rowstoskip -= 1;
5348 : : }
5349 : :
4580 tgl@sss.pgh.pa.us 5350 [ + - ]:CBC 22728 : if (pos >= 0)
5351 : : {
5352 : : /*
5353 : : * Create sample tuple from current result row, and store it in the
5354 : : * position determined above. The tuple has to be created in anl_cxt.
5355 : : */
5356 : 22728 : oldcontext = MemoryContextSwitchTo(astate->anl_cxt);
5357 : :
5358 : 22728 : astate->rows[pos] = make_tuple_from_result_row(res, row,
5359 : : astate->rel,
5360 : : astate->attinmeta,
5361 : : astate->retrieved_attrs,
5362 : : NULL,
5363 : : astate->temp_cxt);
5364 : :
5365 : 22727 : MemoryContextSwitchTo(oldcontext);
5366 : : }
5367 : 22727 : }
5368 : :
5369 : : /*
5370 : : * Import a foreign schema
5371 : : */
5372 : : static List *
4076 5373 : 10 : postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid)
5374 : : {
5375 : 10 : List *commands = NIL;
5376 : 10 : bool import_collate = true;
5377 : 10 : bool import_default = false;
1493 efujita@postgresql.o 5378 : 10 : bool import_generated = true;
4076 tgl@sss.pgh.pa.us 5379 : 10 : bool import_not_null = true;
5380 : : ForeignServer *server;
5381 : : UserMapping *mapping;
5382 : : PGconn *conn;
5383 : : StringInfoData buf;
5384 : : PGresult *res;
5385 : : int numrows,
5386 : : i;
5387 : : ListCell *lc;
5388 : :
5389 : : /* Parse statement options */
5390 [ + + + + : 14 : foreach(lc, stmt->options)
+ + ]
5391 : : {
5392 : 4 : DefElem *def = (DefElem *) lfirst(lc);
5393 : :
5394 [ + + ]: 4 : if (strcmp(def->defname, "import_collate") == 0)
5395 : 1 : import_collate = defGetBoolean(def);
5396 [ + + ]: 3 : else if (strcmp(def->defname, "import_default") == 0)
5397 : 1 : import_default = defGetBoolean(def);
1493 efujita@postgresql.o 5398 [ + + ]: 2 : else if (strcmp(def->defname, "import_generated") == 0)
5399 : 1 : import_generated = defGetBoolean(def);
4076 tgl@sss.pgh.pa.us 5400 [ + - ]: 1 : else if (strcmp(def->defname, "import_not_null") == 0)
5401 : 1 : import_not_null = defGetBoolean(def);
5402 : : else
4076 tgl@sss.pgh.pa.us 5403 [ # # ]:UBC 0 : ereport(ERROR,
5404 : : (errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
5405 : : errmsg("invalid option \"%s\"", def->defname)));
5406 : : }
5407 : :
5408 : : /*
5409 : : * Get connection to the foreign server. Connection manager will
5410 : : * establish new connection if necessary.
5411 : : */
4076 tgl@sss.pgh.pa.us 5412 :CBC 10 : server = GetForeignServer(serverOid);
5413 : 10 : mapping = GetUserMapping(GetUserId(), server->serverid);
1620 efujita@postgresql.o 5414 : 10 : conn = GetConnection(mapping, false, NULL);
5415 : :
5416 : : /* Don't attempt to import collation if remote server hasn't got it */
4076 tgl@sss.pgh.pa.us 5417 [ - + ]: 10 : if (PQserverVersion(conn) < 90100)
4076 tgl@sss.pgh.pa.us 5418 :UBC 0 : import_collate = false;
5419 : :
5420 : : /* Create workspace for strings */
4076 tgl@sss.pgh.pa.us 5421 :CBC 10 : initStringInfo(&buf);
5422 : :
5423 : : /* Check that the schema really exists */
43 tgl@sss.pgh.pa.us 5424 :GNC 10 : appendStringInfoString(&buf, "SELECT 1 FROM pg_catalog.pg_namespace WHERE nspname = ");
5425 : 10 : deparseStringLiteral(&buf, stmt->remote_schema);
5426 : :
5427 : 10 : res = pgfdw_exec_query(conn, buf.data, NULL);
5428 [ - + ]: 10 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 5429 :UNC 0 : pgfdw_report_error(res, conn, buf.data);
5430 : :
43 tgl@sss.pgh.pa.us 5431 [ + + ]:GNC 10 : if (PQntuples(res) != 1)
5432 [ + - ]: 1 : ereport(ERROR,
5433 : : (errcode(ERRCODE_FDW_SCHEMA_NOT_FOUND),
5434 : : errmsg("schema \"%s\" is not present on foreign server \"%s\"",
5435 : : stmt->remote_schema, server->servername)));
5436 : :
5437 : 9 : PQclear(res);
5438 : 9 : resetStringInfo(&buf);
5439 : :
5440 : : /*
5441 : : * Fetch all table data from this schema, possibly restricted by EXCEPT or
5442 : : * LIMIT TO. (We don't actually need to pay any attention to EXCEPT/LIMIT
5443 : : * TO here, because the core code will filter the statements we return
5444 : : * according to those lists anyway. But it should save a few cycles to
5445 : : * not process excluded tables in the first place.)
5446 : : *
5447 : : * Import table data for partitions only when they are explicitly
5448 : : * specified in LIMIT TO clause. Otherwise ignore them and only include
5449 : : * the definitions of the root partitioned tables to allow access to the
5450 : : * complete remote data set locally in the schema imported.
5451 : : *
5452 : : * Note: because we run the connection with search_path restricted to
5453 : : * pg_catalog, the format_type() and pg_get_expr() outputs will always
5454 : : * include a schema name for types/functions in other schemas, which is
5455 : : * what we want.
5456 : : */
5457 : 9 : appendStringInfoString(&buf,
5458 : : "SELECT relname, "
5459 : : " attname, "
5460 : : " format_type(atttypid, atttypmod), "
5461 : : " attnotnull, "
5462 : : " pg_get_expr(adbin, adrelid), ");
5463 : :
5464 : : /* Generated columns are supported since Postgres 12 */
5465 [ + - ]: 9 : if (PQserverVersion(conn) >= 120000)
1493 efujita@postgresql.o 5466 :CBC 9 : appendStringInfoString(&buf,
5467 : : " attgenerated, ");
5468 : : else
1466 tgl@sss.pgh.pa.us 5469 :LBC (9) : appendStringInfoString(&buf,
5470 : : " NULL, ");
5471 : :
43 tgl@sss.pgh.pa.us 5472 [ + + ]:GNC 9 : if (import_collate)
4076 tgl@sss.pgh.pa.us 5473 :CBC 8 : appendStringInfoString(&buf,
5474 : : " collname, "
5475 : : " collnsp.nspname ");
5476 : : else
43 tgl@sss.pgh.pa.us 5477 :GNC 1 : appendStringInfoString(&buf,
5478 : : " NULL, NULL ");
5479 : :
5480 : 9 : appendStringInfoString(&buf,
5481 : : "FROM pg_class c "
5482 : : " JOIN pg_namespace n ON "
5483 : : " relnamespace = n.oid "
5484 : : " LEFT JOIN pg_attribute a ON "
5485 : : " attrelid = c.oid AND attnum > 0 "
5486 : : " AND NOT attisdropped "
5487 : : " LEFT JOIN pg_attrdef ad ON "
5488 : : " adrelid = c.oid AND adnum = attnum ");
5489 : :
5490 [ + + ]: 9 : if (import_collate)
5491 : 8 : appendStringInfoString(&buf,
5492 : : " LEFT JOIN pg_collation coll ON "
5493 : : " coll.oid = attcollation "
5494 : : " LEFT JOIN pg_namespace collnsp ON "
5495 : : " collnsp.oid = collnamespace ");
5496 : :
5497 : 9 : appendStringInfoString(&buf,
5498 : : "WHERE c.relkind IN ("
5499 : : CppAsString2(RELKIND_RELATION) ","
5500 : : CppAsString2(RELKIND_VIEW) ","
5501 : : CppAsString2(RELKIND_FOREIGN_TABLE) ","
5502 : : CppAsString2(RELKIND_MATVIEW) ","
5503 : : CppAsString2(RELKIND_PARTITIONED_TABLE) ") "
5504 : : " AND n.nspname = ");
5505 : 9 : deparseStringLiteral(&buf, stmt->remote_schema);
5506 : :
5507 : : /* Partitions are supported since Postgres 10 */
5508 [ + - ]: 9 : if (PQserverVersion(conn) >= 100000 &&
5509 [ + + ]: 9 : stmt->list_type != FDW_IMPORT_SCHEMA_LIMIT_TO)
5510 : 5 : appendStringInfoString(&buf, " AND NOT c.relispartition ");
5511 : :
5512 : : /* Apply restrictions for LIMIT TO and EXCEPT */
5513 [ + + ]: 9 : if (stmt->list_type == FDW_IMPORT_SCHEMA_LIMIT_TO ||
5514 [ + + ]: 5 : stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
5515 : : {
5516 : 5 : bool first_item = true;
5517 : :
5518 : 5 : appendStringInfoString(&buf, " AND c.relname ");
5519 [ + + ]: 5 : if (stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
5520 : 1 : appendStringInfoString(&buf, "NOT ");
5521 : 5 : appendStringInfoString(&buf, "IN (");
5522 : :
5523 : : /* Append list of table names within IN clause */
5524 [ + - + + : 15 : foreach(lc, stmt->table_list)
+ + ]
5525 : : {
5526 : 10 : RangeVar *rv = (RangeVar *) lfirst(lc);
5527 : :
5528 [ + + ]: 10 : if (first_item)
5529 : 5 : first_item = false;
5530 : : else
5531 : 5 : appendStringInfoString(&buf, ", ");
5532 : 10 : deparseStringLiteral(&buf, rv->relname);
5533 : : }
5534 : 5 : appendStringInfoChar(&buf, ')');
5535 : : }
5536 : :
5537 : : /* Append ORDER BY at the end of query to ensure output ordering */
5538 : 9 : appendStringInfoString(&buf, " ORDER BY c.relname, a.attnum");
5539 : :
5540 : : /* Fetch the data */
5541 : 9 : res = pgfdw_exec_query(conn, buf.data, NULL);
5542 [ - + ]: 9 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
39 tgl@sss.pgh.pa.us 5543 :UNC 0 : pgfdw_report_error(res, conn, buf.data);
5544 : :
5545 : : /* Process results */
43 tgl@sss.pgh.pa.us 5546 :GNC 9 : numrows = PQntuples(res);
5547 : : /* note: incrementation of i happens in inner loop's while() test */
5548 [ + + ]: 47 : for (i = 0; i < numrows;)
5549 : : {
5550 : 38 : char *tablename = PQgetvalue(res, i, 0);
5551 : 38 : bool first_item = true;
5552 : :
5553 : 38 : resetStringInfo(&buf);
5554 : 38 : appendStringInfo(&buf, "CREATE FOREIGN TABLE %s (\n",
5555 : : quote_identifier(tablename));
5556 : :
5557 : : /* Scan all rows for this table */
5558 : : do
5559 : : {
5560 : : char *attname;
5561 : : char *typename;
5562 : : char *attnotnull;
5563 : : char *attgenerated;
5564 : : char *attdefault;
5565 : : char *collname;
5566 : : char *collnamespace;
5567 : :
5568 : : /* If table has no columns, we'll see nulls here */
5569 [ + + ]: 75 : if (PQgetisnull(res, i, 1))
5570 : 5 : continue;
5571 : :
5572 : 70 : attname = PQgetvalue(res, i, 1);
5573 : 70 : typename = PQgetvalue(res, i, 2);
5574 : 70 : attnotnull = PQgetvalue(res, i, 3);
5575 [ + + ]: 70 : attdefault = PQgetisnull(res, i, 4) ? NULL :
5576 : 15 : PQgetvalue(res, i, 4);
5577 [ + - ]: 70 : attgenerated = PQgetisnull(res, i, 5) ? NULL :
5578 : 70 : PQgetvalue(res, i, 5);
5579 [ + + ]: 70 : collname = PQgetisnull(res, i, 6) ? NULL :
5580 : 19 : PQgetvalue(res, i, 6);
5581 [ + + ]: 70 : collnamespace = PQgetisnull(res, i, 7) ? NULL :
5582 : 19 : PQgetvalue(res, i, 7);
5583 : :
5584 [ + + ]: 70 : if (first_item)
5585 : 33 : first_item = false;
5586 : : else
5587 : 37 : appendStringInfoString(&buf, ",\n");
5588 : :
5589 : : /* Print column name and type */
5590 : 70 : appendStringInfo(&buf, " %s %s",
5591 : : quote_identifier(attname),
5592 : : typename);
5593 : :
5594 : : /*
5595 : : * Add column_name option so that renaming the foreign table's
5596 : : * column doesn't break the association to the underlying column.
5597 : : */
5598 : 70 : appendStringInfoString(&buf, " OPTIONS (column_name ");
5599 : 70 : deparseStringLiteral(&buf, attname);
5600 : 70 : appendStringInfoChar(&buf, ')');
5601 : :
5602 : : /* Add COLLATE if needed */
5603 [ + + + + : 70 : if (import_collate && collname != NULL && collnamespace != NULL)
+ - ]
5604 : 19 : appendStringInfo(&buf, " COLLATE %s.%s",
5605 : : quote_identifier(collnamespace),
5606 : : quote_identifier(collname));
5607 : :
5608 : : /* Add DEFAULT if needed */
5609 [ + + + + : 70 : if (import_default && attdefault != NULL &&
+ - ]
5610 [ + + ]: 3 : (!attgenerated || !attgenerated[0]))
5611 : 2 : appendStringInfo(&buf, " DEFAULT %s", attdefault);
5612 : :
5613 : : /* Add GENERATED if needed */
5614 [ + + + - ]: 70 : if (import_generated && attgenerated != NULL &&
5615 [ + + ]: 57 : attgenerated[0] == ATTRIBUTE_GENERATED_STORED)
5616 : : {
5617 [ - + ]: 4 : Assert(attdefault != NULL);
5618 : 4 : appendStringInfo(&buf,
5619 : : " GENERATED ALWAYS AS (%s) STORED",
5620 : : attdefault);
5621 : : }
5622 : :
5623 : : /* Add NOT NULL if needed */
5624 [ + + + + ]: 70 : if (import_not_null && attnotnull[0] == 't')
5625 : 4 : appendStringInfoString(&buf, " NOT NULL");
5626 : : }
5627 [ + + ]: 75 : while (++i < numrows &&
5628 [ + + ]: 66 : strcmp(PQgetvalue(res, i, 0), tablename) == 0);
5629 : :
5630 : : /*
5631 : : * Add server name and table-level options. We specify remote schema
5632 : : * and table name as options (the latter to ensure that renaming the
5633 : : * foreign table doesn't break the association).
5634 : : */
5635 : 38 : appendStringInfo(&buf, "\n) SERVER %s\nOPTIONS (",
5636 : 38 : quote_identifier(server->servername));
5637 : :
5638 : 38 : appendStringInfoString(&buf, "schema_name ");
5639 : 38 : deparseStringLiteral(&buf, stmt->remote_schema);
5640 : 38 : appendStringInfoString(&buf, ", table_name ");
5641 : 38 : deparseStringLiteral(&buf, tablename);
5642 : :
5643 : 38 : appendStringInfoString(&buf, ");");
5644 : :
5645 : 38 : commands = lappend(commands, pstrdup(buf.data));
5646 : : }
5647 : 9 : PQclear(res);
5648 : :
4076 tgl@sss.pgh.pa.us 5649 :CBC 9 : ReleaseConnection(conn);
5650 : :
5651 : 9 : return commands;
5652 : : }
5653 : :
5654 : : /*
5655 : : * Check if reltarget is safe enough to push down semi-join. Reltarget is not
5656 : : * safe, if it contains references to inner rel relids, which do not belong to
5657 : : * outer rel.
5658 : : */
5659 : : static bool
641 akorotkov@postgresql 5660 : 64 : semijoin_target_ok(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel)
5661 : : {
5662 : : List *vars;
5663 : : ListCell *lc;
5664 : 64 : bool ok = true;
5665 : :
5666 [ - + ]: 64 : Assert(joinrel->reltarget);
5667 : :
5668 : 64 : vars = pull_var_clause((Node *) joinrel->reltarget->exprs, PVC_INCLUDE_PLACEHOLDERS);
5669 : :
5670 [ + - + + : 443 : foreach(lc, vars)
+ + ]
5671 : : {
5672 : 394 : Var *var = (Var *) lfirst(lc);
5673 : :
5674 [ - + ]: 394 : if (!IsA(var, Var))
641 akorotkov@postgresql 5675 :UBC 0 : continue;
5676 : :
165 akorotkov@postgresql 5677 [ + + ]:CBC 394 : if (bms_is_member(var->varno, innerrel->relids))
5678 : : {
5679 : : /*
5680 : : * The planner can create semi-join, which refers to inner rel
5681 : : * vars in its target list. However, we deparse semi-join as an
5682 : : * exists() subquery, so can't handle references to inner rel in
5683 : : * the target list.
5684 : : */
5685 [ - + ]: 15 : Assert(!bms_is_member(var->varno, outerrel->relids));
641 5686 : 15 : ok = false;
5687 : 15 : break;
5688 : : }
5689 : : }
5690 : 64 : return ok;
5691 : : }
5692 : :
5693 : : /*
5694 : : * Assess whether the join between inner and outer relations can be pushed down
5695 : : * to the foreign server. As a side effect, save information we obtain in this
5696 : : * function to PgFdwRelationInfo passed in.
5697 : : */
5698 : : static bool
3497 rhaas@postgresql.org 5699 : 392 : foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype,
5700 : : RelOptInfo *outerrel, RelOptInfo *innerrel,
5701 : : JoinPathExtraData *extra)
5702 : : {
5703 : : PgFdwRelationInfo *fpinfo;
5704 : : PgFdwRelationInfo *fpinfo_o;
5705 : : PgFdwRelationInfo *fpinfo_i;
5706 : : ListCell *lc;
5707 : : List *joinclauses;
5708 : :
5709 : : /*
5710 : : * We support pushing down INNER, LEFT, RIGHT, FULL OUTER and SEMI joins.
5711 : : * Constructing queries representing ANTI joins is hard, hence not
5712 : : * considered right now.
5713 : : */
5714 [ + + + + : 392 : if (jointype != JOIN_INNER && jointype != JOIN_LEFT &&
+ - ]
641 akorotkov@postgresql 5715 [ + + + + ]: 129 : jointype != JOIN_RIGHT && jointype != JOIN_FULL &&
5716 : : jointype != JOIN_SEMI)
5717 : 19 : return false;
5718 : :
5719 : : /*
5720 : : * We can't push down semi-join if its reltarget is not safe
5721 : : */
5722 [ + + + + ]: 373 : if ((jointype == JOIN_SEMI) && !semijoin_target_ok(root, joinrel, outerrel, innerrel))
3497 rhaas@postgresql.org 5723 : 15 : return false;
5724 : :
5725 : : /*
5726 : : * If either of the joining relations is marked as unsafe to pushdown, the
5727 : : * join can not be pushed down.
5728 : : */
5729 : 358 : fpinfo = (PgFdwRelationInfo *) joinrel->fdw_private;
5730 : 358 : fpinfo_o = (PgFdwRelationInfo *) outerrel->fdw_private;
5731 : 358 : fpinfo_i = (PgFdwRelationInfo *) innerrel->fdw_private;
5732 [ + - + + : 358 : if (!fpinfo_o || !fpinfo_o->pushdown_safe ||
+ - ]
5733 [ - + ]: 353 : !fpinfo_i || !fpinfo_i->pushdown_safe)
5734 : 5 : return false;
5735 : :
5736 : : /*
5737 : : * If joining relations have local conditions, those conditions are
5738 : : * required to be applied before joining the relations. Hence the join can
5739 : : * not be pushed down.
5740 : : */
5741 [ + + + + ]: 353 : if (fpinfo_o->local_conds || fpinfo_i->local_conds)
5742 : 9 : return false;
5743 : :
5744 : : /*
5745 : : * Merge FDW options. We might be tempted to do this after we have deemed
5746 : : * the foreign join to be OK. But we must do this beforehand so that we
5747 : : * know which quals can be evaluated on the foreign server, which might
5748 : : * depend on shippable_extensions.
5749 : : */
3057 peter_e@gmx.net 5750 : 344 : fpinfo->server = fpinfo_o->server;
5751 : 344 : merge_fdw_options(fpinfo, fpinfo_o, fpinfo_i);
5752 : :
5753 : : /*
5754 : : * Separate restrict list into join quals and pushed-down (other) quals.
5755 : : *
5756 : : * Join quals belonging to an outer join must all be shippable, else we
5757 : : * cannot execute the join remotely. Add such quals to 'joinclauses'.
5758 : : *
5759 : : * Add other quals to fpinfo->remote_conds if they are shippable, else to
5760 : : * fpinfo->local_conds. In an inner join it's okay to execute conditions
5761 : : * either locally or remotely; the same is true for pushed-down conditions
5762 : : * at an outer join.
5763 : : *
5764 : : * Note we might return failure after having already scribbled on
5765 : : * fpinfo->remote_conds and fpinfo->local_conds. That's okay because we
5766 : : * won't consult those lists again if we deem the join unshippable.
5767 : : */
3070 tgl@sss.pgh.pa.us 5768 : 344 : joinclauses = NIL;
5769 [ + + + + : 685 : foreach(lc, extra->restrictlist)
+ + ]
5770 : : {
5771 : 344 : RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
5772 : 344 : bool is_remote_clause = is_foreign_expr(root, joinrel,
5773 : : rinfo->clause);
5774 : :
2696 5775 [ + + ]: 344 : if (IS_OUTER_JOIN(jointype) &&
5776 [ + + + - ]: 129 : !RINFO_IS_PUSHED_DOWN(rinfo, joinrel->relids))
5777 : : {
3070 5778 [ + + ]: 113 : if (!is_remote_clause)
5779 : 3 : return false;
5780 : 110 : joinclauses = lappend(joinclauses, rinfo);
5781 : : }
5782 : : else
5783 : : {
5784 [ + + ]: 231 : if (is_remote_clause)
5785 : 219 : fpinfo->remote_conds = lappend(fpinfo->remote_conds, rinfo);
5786 : : else
5787 : 12 : fpinfo->local_conds = lappend(fpinfo->local_conds, rinfo);
5788 : : }
5789 : : }
5790 : :
5791 : : /*
5792 : : * deparseExplicitTargetList() isn't smart enough to handle anything other
5793 : : * than a Var. In particular, if there's some PlaceHolderVar that would
5794 : : * need to be evaluated within this join tree (because there's an upper
5795 : : * reference to a quantity that may go to NULL as a result of an outer
5796 : : * join), then we can't try to push the join down because we'll fail when
5797 : : * we get to deparseExplicitTargetList(). However, a PlaceHolderVar that
5798 : : * needs to be evaluated *at the top* of this join tree is OK, because we
5799 : : * can do that locally after fetching the results from the remote side.
5800 : : */
3371 rhaas@postgresql.org 5801 [ + + + + : 344 : foreach(lc, root->placeholder_list)
+ + ]
5802 : : {
5803 : 11 : PlaceHolderInfo *phinfo = lfirst(lc);
5804 : : Relids relids;
5805 : :
5806 : : /* PlaceHolderInfo refers to parent relids, not child relids. */
2753 5807 [ + + - + ]: 11 : relids = IS_OTHER_REL(joinrel) ?
5808 [ + - ]: 22 : joinrel->top_parent_relids : joinrel->relids;
5809 : :
3371 5810 [ + - + + ]: 22 : if (bms_is_subset(phinfo->ph_eval_at, relids) &&
5811 : 11 : bms_nonempty_difference(relids, phinfo->ph_eval_at))
5812 : 8 : return false;
5813 : : }
5814 : :
5815 : : /* Save the join clauses, for later use. */
3497 5816 : 333 : fpinfo->joinclauses = joinclauses;
5817 : :
5818 : 333 : fpinfo->outerrel = outerrel;
5819 : 333 : fpinfo->innerrel = innerrel;
5820 : 333 : fpinfo->jointype = jointype;
5821 : :
5822 : : /*
5823 : : * By default, both the input relations are not required to be deparsed as
5824 : : * subqueries, but there might be some relations covered by the input
5825 : : * relations that are required to be deparsed as subqueries, so save the
5826 : : * relids of those relations for later use by the deparser.
5827 : : */
3096 5828 : 333 : fpinfo->make_outerrel_subquery = false;
5829 : 333 : fpinfo->make_innerrel_subquery = false;
5830 [ - + ]: 333 : Assert(bms_is_subset(fpinfo_o->lower_subquery_rels, outerrel->relids));
5831 [ - + ]: 333 : Assert(bms_is_subset(fpinfo_i->lower_subquery_rels, innerrel->relids));
5832 : 666 : fpinfo->lower_subquery_rels = bms_union(fpinfo_o->lower_subquery_rels,
5833 : 333 : fpinfo_i->lower_subquery_rels);
641 akorotkov@postgresql 5834 : 666 : fpinfo->hidden_subquery_rels = bms_union(fpinfo_o->hidden_subquery_rels,
5835 : 333 : fpinfo_i->hidden_subquery_rels);
5836 : :
5837 : : /*
5838 : : * Pull the other remote conditions from the joining relations into join
5839 : : * clauses or other remote clauses (remote_conds) of this relation
5840 : : * wherever possible. This avoids building subqueries at every join step.
5841 : : *
5842 : : * For an inner join, clauses from both the relations are added to the
5843 : : * other remote clauses. For LEFT and RIGHT OUTER join, the clauses from
5844 : : * the outer side are added to remote_conds since those can be evaluated
5845 : : * after the join is evaluated. The clauses from inner side are added to
5846 : : * the joinclauses, since they need to be evaluated while constructing the
5847 : : * join.
5848 : : *
5849 : : * For SEMI-JOIN clauses from inner relation can not be added to
5850 : : * remote_conds, but should be treated as join clauses (as they are
5851 : : * deparsed to EXISTS subquery, where inner relation can be referred). A
5852 : : * list of relation ids, which can't be referred to from higher levels, is
5853 : : * preserved as a hidden_subquery_rels list.
5854 : : *
5855 : : * For a FULL OUTER JOIN, the other clauses from either relation can not
5856 : : * be added to the joinclauses or remote_conds, since each relation acts
5857 : : * as an outer relation for the other.
5858 : : *
5859 : : * The joining sides can not have local conditions, thus no need to test
5860 : : * shippability of the clauses being pulled up.
5861 : : */
3497 rhaas@postgresql.org 5862 [ + + - + : 333 : switch (jointype)
+ - ]
5863 : : {
5864 : 187 : case JOIN_INNER:
5865 : 374 : fpinfo->remote_conds = list_concat(fpinfo->remote_conds,
2217 tgl@sss.pgh.pa.us 5866 : 187 : fpinfo_i->remote_conds);
3497 rhaas@postgresql.org 5867 : 374 : fpinfo->remote_conds = list_concat(fpinfo->remote_conds,
2217 tgl@sss.pgh.pa.us 5868 : 187 : fpinfo_o->remote_conds);
3497 rhaas@postgresql.org 5869 : 187 : break;
5870 : :
5871 : 60 : case JOIN_LEFT:
5872 : :
5873 : : /*
5874 : : * When semi-join is involved in the inner or outer part of the
5875 : : * left join, it's deparsed as a subquery, and we can't refer to
5876 : : * its vars on the upper level.
5877 : : */
165 akorotkov@postgresql 5878 [ + + ]: 60 : if (bms_is_empty(fpinfo_i->hidden_subquery_rels))
5879 : 56 : fpinfo->joinclauses = list_concat(fpinfo->joinclauses,
5880 : 56 : fpinfo_i->remote_conds);
5881 [ + - ]: 60 : if (bms_is_empty(fpinfo_o->hidden_subquery_rels))
5882 : 60 : fpinfo->remote_conds = list_concat(fpinfo->remote_conds,
5883 : 60 : fpinfo_o->remote_conds);
3497 rhaas@postgresql.org 5884 : 60 : break;
5885 : :
3497 rhaas@postgresql.org 5886 :UBC 0 : case JOIN_RIGHT:
5887 : :
5888 : : /*
5889 : : * When semi-join is involved in the inner or outer part of the
5890 : : * right join, it's deparsed as a subquery, and we can't refer to
5891 : : * its vars on the upper level.
5892 : : */
165 akorotkov@postgresql 5893 [ # # ]: 0 : if (bms_is_empty(fpinfo_o->hidden_subquery_rels))
5894 : 0 : fpinfo->joinclauses = list_concat(fpinfo->joinclauses,
5895 : 0 : fpinfo_o->remote_conds);
5896 [ # # ]: 0 : if (bms_is_empty(fpinfo_i->hidden_subquery_rels))
5897 : 0 : fpinfo->remote_conds = list_concat(fpinfo->remote_conds,
5898 : 0 : fpinfo_i->remote_conds);
3497 rhaas@postgresql.org 5899 : 0 : break;
5900 : :
641 akorotkov@postgresql 5901 :CBC 44 : case JOIN_SEMI:
5902 : 88 : fpinfo->joinclauses = list_concat(fpinfo->joinclauses,
5903 : 44 : fpinfo_i->remote_conds);
5904 : 88 : fpinfo->joinclauses = list_concat(fpinfo->joinclauses,
5905 : 44 : fpinfo->remote_conds);
5906 : 44 : fpinfo->remote_conds = list_copy(fpinfo_o->remote_conds);
5907 : 88 : fpinfo->hidden_subquery_rels = bms_union(fpinfo->hidden_subquery_rels,
5908 : 44 : innerrel->relids);
5909 : 44 : break;
5910 : :
3497 rhaas@postgresql.org 5911 : 42 : case JOIN_FULL:
5912 : :
5913 : : /*
5914 : : * In this case, if any of the input relations has conditions, we
5915 : : * need to deparse that relation as a subquery so that the
5916 : : * conditions can be evaluated before the join. Remember it in
5917 : : * the fpinfo of this relation so that the deparser can take
5918 : : * appropriate action. Also, save the relids of base relations
5919 : : * covered by that relation for later use by the deparser.
5920 : : */
3096 5921 [ + + ]: 42 : if (fpinfo_o->remote_conds)
5922 : : {
5923 : 14 : fpinfo->make_outerrel_subquery = true;
5924 : 14 : fpinfo->lower_subquery_rels =
5925 : 14 : bms_add_members(fpinfo->lower_subquery_rels,
5926 : 14 : outerrel->relids);
5927 : : }
5928 [ + + ]: 42 : if (fpinfo_i->remote_conds)
5929 : : {
5930 : 14 : fpinfo->make_innerrel_subquery = true;
5931 : 14 : fpinfo->lower_subquery_rels =
5932 : 14 : bms_add_members(fpinfo->lower_subquery_rels,
5933 : 14 : innerrel->relids);
5934 : : }
3497 5935 : 42 : break;
5936 : :
3497 rhaas@postgresql.org 5937 :UBC 0 : default:
5938 : : /* Should not happen, we have just checked this above */
5939 [ # # ]: 0 : elog(ERROR, "unsupported join type %d", jointype);
5940 : : }
5941 : :
5942 : : /*
5943 : : * For an inner join, all restrictions can be treated alike. Treating the
5944 : : * pushed down conditions as join conditions allows a top level full outer
5945 : : * join to be deparsed without requiring subqueries.
5946 : : */
3426 rhaas@postgresql.org 5947 [ + + ]:CBC 333 : if (jointype == JOIN_INNER)
5948 : : {
5949 [ - + ]: 187 : Assert(!fpinfo->joinclauses);
5950 : 187 : fpinfo->joinclauses = fpinfo->remote_conds;
5951 : 187 : fpinfo->remote_conds = NIL;
5952 : : }
641 akorotkov@postgresql 5953 [ + + + - : 146 : else if (jointype == JOIN_LEFT || jointype == JOIN_RIGHT || jointype == JOIN_FULL)
+ + ]
5954 : : {
5955 : : /*
5956 : : * Conditions, generated from semi-joins, should be evaluated before
5957 : : * LEFT/RIGHT/FULL join.
5958 : : */
5959 [ - + ]: 102 : if (!bms_is_empty(fpinfo_o->hidden_subquery_rels))
5960 : : {
641 akorotkov@postgresql 5961 :UBC 0 : fpinfo->make_outerrel_subquery = true;
5962 : 0 : fpinfo->lower_subquery_rels = bms_add_members(fpinfo->lower_subquery_rels, outerrel->relids);
5963 : : }
5964 : :
641 akorotkov@postgresql 5965 [ + + ]:CBC 102 : if (!bms_is_empty(fpinfo_i->hidden_subquery_rels))
5966 : : {
5967 : 4 : fpinfo->make_innerrel_subquery = true;
5968 : 4 : fpinfo->lower_subquery_rels = bms_add_members(fpinfo->lower_subquery_rels, innerrel->relids);
5969 : : }
5970 : : }
5971 : :
5972 : : /* Mark that this join can be pushed down safely */
3426 rhaas@postgresql.org 5973 : 333 : fpinfo->pushdown_safe = true;
5974 : :
5975 : : /* Get user mapping */
3340 tgl@sss.pgh.pa.us 5976 [ + + ]: 333 : if (fpinfo->use_remote_estimate)
5977 : : {
5978 [ + + ]: 221 : if (fpinfo_o->use_remote_estimate)
5979 : 155 : fpinfo->user = fpinfo_o->user;
5980 : : else
5981 : 66 : fpinfo->user = fpinfo_i->user;
5982 : : }
5983 : : else
5984 : 112 : fpinfo->user = NULL;
5985 : :
5986 : : /*
5987 : : * Set # of retrieved rows and cached relation costs to some negative
5988 : : * value, so that we can detect when they are set to some sensible values,
5989 : : * during one (usually the first) of the calls to estimate_path_cost_size.
5990 : : */
2276 efujita@postgresql.o 5991 : 333 : fpinfo->retrieved_rows = -1;
3426 rhaas@postgresql.org 5992 : 333 : fpinfo->rel_startup_cost = -1;
5993 : 333 : fpinfo->rel_total_cost = -1;
5994 : :
5995 : : /*
5996 : : * Set the string describing this join relation to be used in EXPLAIN
5997 : : * output of corresponding ForeignScan. Note that the decoration we add
5998 : : * to the base relation names mustn't include any digits, or it'll confuse
5999 : : * postgresExplainForeignScan.
6000 : : */
2105 tgl@sss.pgh.pa.us 6001 : 333 : fpinfo->relation_name = psprintf("(%s) %s JOIN (%s)",
6002 : : fpinfo_o->relation_name,
6003 : : get_jointype_name(fpinfo->jointype),
6004 : : fpinfo_i->relation_name);
6005 : :
6006 : : /*
6007 : : * Set the relation index. This is defined as the position of this
6008 : : * joinrel in the join_rel_list list plus the length of the rtable list.
6009 : : * Note that since this joinrel is at the end of the join_rel_list list
6010 : : * when we are called, we can get the position by list_length.
6011 : : */
2999 6012 [ - + ]: 333 : Assert(fpinfo->relation_index == 0); /* shouldn't be set yet */
3096 rhaas@postgresql.org 6013 : 333 : fpinfo->relation_index =
6014 : 333 : list_length(root->parse->rtable) + list_length(root->join_rel_list);
6015 : :
3497 6016 : 333 : return true;
6017 : : }
6018 : :
6019 : : static void
3468 6020 : 1515 : add_paths_with_pathkeys_for_rel(PlannerInfo *root, RelOptInfo *rel,
6021 : : Path *epq_path, List *restrictlist)
6022 : : {
2999 tgl@sss.pgh.pa.us 6023 : 1515 : List *useful_pathkeys_list = NIL; /* List of all pathkeys */
6024 : : ListCell *lc;
6025 : :
3468 rhaas@postgresql.org 6026 : 1515 : useful_pathkeys_list = get_useful_pathkeys_for_relation(root, rel);
6027 : :
6028 : : /*
6029 : : * Before creating sorted paths, arrange for the passed-in EPQ path, if
6030 : : * any, to return columns needed by the parent ForeignScan node so that
6031 : : * they will propagate up through Sort nodes injected below, if necessary.
6032 : : */
1088 efujita@postgresql.o 6033 [ + + + + ]: 1515 : if (epq_path != NULL && useful_pathkeys_list != NIL)
6034 : : {
6035 : 32 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) rel->fdw_private;
6036 : 32 : PathTarget *target = copy_pathtarget(epq_path->pathtarget);
6037 : :
6038 : : /* Include columns required for evaluating PHVs in the tlist. */
6039 : 32 : add_new_columns_to_pathtarget(target,
6040 : 32 : pull_var_clause((Node *) target->exprs,
6041 : : PVC_RECURSE_PLACEHOLDERS));
6042 : :
6043 : : /* Include columns required for evaluating the local conditions. */
6044 [ + + + + : 35 : foreach(lc, fpinfo->local_conds)
+ + ]
6045 : : {
6046 : 3 : RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
6047 : :
6048 : 3 : add_new_columns_to_pathtarget(target,
6049 : 3 : pull_var_clause((Node *) rinfo->clause,
6050 : : PVC_RECURSE_PLACEHOLDERS));
6051 : : }
6052 : :
6053 : : /*
6054 : : * If we have added any new columns, adjust the tlist of the EPQ path.
6055 : : *
6056 : : * Note: the plan created using this path will only be used to execute
6057 : : * EPQ checks, where accuracy of the plan cost and width estimates
6058 : : * would not be important, so we do not do set_pathtarget_cost_width()
6059 : : * for the new pathtarget here. See also postgresGetForeignPlan().
6060 : : */
6061 [ + + ]: 32 : if (list_length(target->exprs) > list_length(epq_path->pathtarget->exprs))
6062 : : {
6063 : : /* The EPQ path is a join path, so it is projection-capable. */
6064 [ - + ]: 4 : Assert(is_projection_capable_path(epq_path));
6065 : :
6066 : : /*
6067 : : * Use create_projection_path() here, so as to avoid modifying it
6068 : : * in place.
6069 : : */
6070 : 4 : epq_path = (Path *) create_projection_path(root,
6071 : : rel,
6072 : : epq_path,
6073 : : target);
6074 : : }
6075 : : }
6076 : :
6077 : : /* Create one path for each set of pathkeys we found above. */
3468 rhaas@postgresql.org 6078 [ + + + + : 2203 : foreach(lc, useful_pathkeys_list)
+ + ]
6079 : : {
6080 : : double rows;
6081 : : int width;
6082 : : int disabled_nodes;
6083 : : Cost startup_cost;
6084 : : Cost total_cost;
6085 : 688 : List *useful_pathkeys = lfirst(lc);
6086 : : Path *sorted_epq_path;
6087 : :
2349 efujita@postgresql.o 6088 : 688 : estimate_path_cost_size(root, rel, NIL, useful_pathkeys, NULL,
6089 : : &rows, &width, &disabled_nodes,
6090 : : &startup_cost, &total_cost);
6091 : :
6092 : : /*
6093 : : * The EPQ path must be at least as well sorted as the path itself, in
6094 : : * case it gets used as input to a mergejoin.
6095 : : */
2789 rhaas@postgresql.org 6096 : 688 : sorted_epq_path = epq_path;
6097 [ + + ]: 688 : if (sorted_epq_path != NULL &&
6098 [ + + ]: 32 : !pathkeys_contained_in(useful_pathkeys,
6099 : : sorted_epq_path->pathkeys))
6100 : : sorted_epq_path = (Path *)
6101 : 26 : create_sort_path(root,
6102 : : rel,
6103 : : sorted_epq_path,
6104 : : useful_pathkeys,
6105 : : -1.0);
6106 : :
2403 tgl@sss.pgh.pa.us 6107 [ + + + + ]: 688 : if (IS_SIMPLE_REL(rel))
6108 : 421 : add_path(rel, (Path *)
6109 : 421 : create_foreignscan_path(root, rel,
6110 : : NULL,
6111 : : rows,
6112 : : disabled_nodes,
6113 : : startup_cost,
6114 : : total_cost,
6115 : : useful_pathkeys,
6116 : : rel->lateral_relids,
6117 : : sorted_epq_path,
6118 : : NIL, /* no fdw_restrictinfo
6119 : : * list */
6120 : : NIL));
6121 : : else
6122 : 267 : add_path(rel, (Path *)
6123 : 267 : create_foreign_join_path(root, rel,
6124 : : NULL,
6125 : : rows,
6126 : : disabled_nodes,
6127 : : startup_cost,
6128 : : total_cost,
6129 : : useful_pathkeys,
6130 : : rel->lateral_relids,
6131 : : sorted_epq_path,
6132 : : restrictlist,
6133 : : NIL));
6134 : : }
3468 rhaas@postgresql.org 6135 : 1515 : }
6136 : :
6137 : : /*
6138 : : * Parse options from foreign server and apply them to fpinfo.
6139 : : *
6140 : : * New options might also require tweaking merge_fdw_options().
6141 : : */
6142 : : static void
3057 peter_e@gmx.net 6143 : 1184 : apply_server_options(PgFdwRelationInfo *fpinfo)
6144 : : {
6145 : : ListCell *lc;
6146 : :
6147 [ + - + + : 4997 : foreach(lc, fpinfo->server->options)
+ + ]
6148 : : {
6149 : 3813 : DefElem *def = (DefElem *) lfirst(lc);
6150 : :
6151 [ + + ]: 3813 : if (strcmp(def->defname, "use_remote_estimate") == 0)
6152 : 104 : fpinfo->use_remote_estimate = defGetBoolean(def);
6153 [ + + ]: 3709 : else if (strcmp(def->defname, "fdw_startup_cost") == 0)
1522 fujii@postgresql.org 6154 : 6 : (void) parse_real(defGetString(def), &fpinfo->fdw_startup_cost, 0,
6155 : : NULL);
3057 peter_e@gmx.net 6156 [ + + ]: 3703 : else if (strcmp(def->defname, "fdw_tuple_cost") == 0)
1522 fujii@postgresql.org 6157 : 2 : (void) parse_real(defGetString(def), &fpinfo->fdw_tuple_cost, 0,
6158 : : NULL);
3057 peter_e@gmx.net 6159 [ + + ]: 3701 : else if (strcmp(def->defname, "extensions") == 0)
6160 : 928 : fpinfo->shippable_extensions =
6161 : 928 : ExtractExtensionList(defGetString(def), false);
6162 [ - + ]: 2773 : else if (strcmp(def->defname, "fetch_size") == 0)
1522 fujii@postgresql.org 6163 :UBC 0 : (void) parse_int(defGetString(def), &fpinfo->fetch_size, 0, NULL);
1620 efujita@postgresql.o 6164 [ + + ]:CBC 2773 : else if (strcmp(def->defname, "async_capable") == 0)
6165 : 121 : fpinfo->async_capable = defGetBoolean(def);
6166 : : }
3057 peter_e@gmx.net 6167 : 1184 : }
6168 : :
6169 : : /*
6170 : : * Parse options from foreign table and apply them to fpinfo.
6171 : : *
6172 : : * New options might also require tweaking merge_fdw_options().
6173 : : */
6174 : : static void
6175 : 1184 : apply_table_options(PgFdwRelationInfo *fpinfo)
6176 : : {
6177 : : ListCell *lc;
6178 : :
6179 [ + - + + : 3457 : foreach(lc, fpinfo->table->options)
+ + ]
6180 : : {
6181 : 2273 : DefElem *def = (DefElem *) lfirst(lc);
6182 : :
6183 [ + + ]: 2273 : if (strcmp(def->defname, "use_remote_estimate") == 0)
6184 : 348 : fpinfo->use_remote_estimate = defGetBoolean(def);
6185 [ - + ]: 1925 : else if (strcmp(def->defname, "fetch_size") == 0)
1522 fujii@postgresql.org 6186 :UBC 0 : (void) parse_int(defGetString(def), &fpinfo->fetch_size, 0, NULL);
1620 efujita@postgresql.o 6187 [ - + ]:CBC 1925 : else if (strcmp(def->defname, "async_capable") == 0)
1620 efujita@postgresql.o 6188 :UBC 0 : fpinfo->async_capable = defGetBoolean(def);
6189 : : }
3057 peter_e@gmx.net 6190 :CBC 1184 : }
6191 : :
6192 : : /*
6193 : : * Merge FDW options from input relations into a new set of options for a join
6194 : : * or an upper rel.
6195 : : *
6196 : : * For a join relation, FDW-specific information about the inner and outer
6197 : : * relations is provided using fpinfo_i and fpinfo_o. For an upper relation,
6198 : : * fpinfo_o provides the information for the input relation; fpinfo_i is
6199 : : * expected to NULL.
6200 : : */
6201 : : static void
6202 : 789 : merge_fdw_options(PgFdwRelationInfo *fpinfo,
6203 : : const PgFdwRelationInfo *fpinfo_o,
6204 : : const PgFdwRelationInfo *fpinfo_i)
6205 : : {
6206 : : /* We must always have fpinfo_o. */
6207 [ - + ]: 789 : Assert(fpinfo_o);
6208 : :
6209 : : /* fpinfo_i may be NULL, but if present the servers must both match. */
6210 [ + + - + ]: 789 : Assert(!fpinfo_i ||
6211 : : fpinfo_i->server->serverid == fpinfo_o->server->serverid);
6212 : :
6213 : : /*
6214 : : * Copy the server specific FDW options. (For a join, both relations come
6215 : : * from the same server, so the server options should have the same value
6216 : : * for both relations.)
6217 : : */
6218 : 789 : fpinfo->fdw_startup_cost = fpinfo_o->fdw_startup_cost;
6219 : 789 : fpinfo->fdw_tuple_cost = fpinfo_o->fdw_tuple_cost;
6220 : 789 : fpinfo->shippable_extensions = fpinfo_o->shippable_extensions;
6221 : 789 : fpinfo->use_remote_estimate = fpinfo_o->use_remote_estimate;
6222 : 789 : fpinfo->fetch_size = fpinfo_o->fetch_size;
1620 efujita@postgresql.o 6223 : 789 : fpinfo->async_capable = fpinfo_o->async_capable;
6224 : :
6225 : : /* Merge the table level options from either side of the join. */
3057 peter_e@gmx.net 6226 [ + + ]: 789 : if (fpinfo_i)
6227 : : {
6228 : : /*
6229 : : * We'll prefer to use remote estimates for this join if any table
6230 : : * from either side of the join is using remote estimates. This is
6231 : : * most likely going to be preferred since they're already willing to
6232 : : * pay the price of a round trip to get the remote EXPLAIN. In any
6233 : : * case it's not entirely clear how we might otherwise handle this
6234 : : * best.
6235 : : */
6236 [ + + ]: 528 : fpinfo->use_remote_estimate = fpinfo_o->use_remote_estimate ||
3034 bruce@momjian.us 6237 [ + + ]: 184 : fpinfo_i->use_remote_estimate;
6238 : :
6239 : : /*
6240 : : * Set fetch size to maximum of the joining sides, since we are
6241 : : * expecting the rows returned by the join to be proportional to the
6242 : : * relation sizes.
6243 : : */
3057 peter_e@gmx.net 6244 : 344 : fpinfo->fetch_size = Max(fpinfo_o->fetch_size, fpinfo_i->fetch_size);
6245 : :
6246 : : /*
6247 : : * We'll prefer to consider this join async-capable if any table from
6248 : : * either side of the join is considered async-capable. This would be
6249 : : * reasonable because in that case the foreign server would have its
6250 : : * own resources to scan that table asynchronously, and the join could
6251 : : * also be computed asynchronously using the resources.
6252 : : */
1620 efujita@postgresql.o 6253 [ + + ]: 680 : fpinfo->async_capable = fpinfo_o->async_capable ||
6254 [ - + ]: 336 : fpinfo_i->async_capable;
6255 : : }
3057 peter_e@gmx.net 6256 : 789 : }
6257 : :
6258 : : /*
6259 : : * postgresGetForeignJoinPaths
6260 : : * Add possible ForeignPath to joinrel, if join is safe to push down.
6261 : : */
6262 : : static void
3497 rhaas@postgresql.org 6263 : 1352 : postgresGetForeignJoinPaths(PlannerInfo *root,
6264 : : RelOptInfo *joinrel,
6265 : : RelOptInfo *outerrel,
6266 : : RelOptInfo *innerrel,
6267 : : JoinType jointype,
6268 : : JoinPathExtraData *extra)
6269 : : {
6270 : : PgFdwRelationInfo *fpinfo;
6271 : : ForeignPath *joinpath;
6272 : : double rows;
6273 : : int width;
6274 : : int disabled_nodes;
6275 : : Cost startup_cost;
6276 : : Cost total_cost;
6277 : : Path *epq_path; /* Path to create plan to be executed when
6278 : : * EvalPlanQual gets triggered. */
6279 : :
6280 : : /*
6281 : : * Skip if this join combination has been considered already.
6282 : : */
6283 [ + + ]: 1352 : if (joinrel->fdw_private)
6284 : 1019 : return;
6285 : :
6286 : : /*
6287 : : * This code does not work for joins with lateral references, since those
6288 : : * must have parameterized paths, which we don't generate yet.
6289 : : */
2403 tgl@sss.pgh.pa.us 6290 [ + + ]: 396 : if (!bms_is_empty(joinrel->lateral_relids))
6291 : 4 : return;
6292 : :
6293 : : /*
6294 : : * Create unfinished PgFdwRelationInfo entry which is used to indicate
6295 : : * that the join relation is already considered, so that we won't waste
6296 : : * time in judging safety of join pushdown and adding the same paths again
6297 : : * if found safe. Once we know that this join can be pushed down, we fill
6298 : : * the entry.
6299 : : */
3497 rhaas@postgresql.org 6300 : 392 : fpinfo = (PgFdwRelationInfo *) palloc0(sizeof(PgFdwRelationInfo));
6301 : 392 : fpinfo->pushdown_safe = false;
6302 : 392 : joinrel->fdw_private = fpinfo;
6303 : : /* attrs_used is only for base relations. */
6304 : 392 : fpinfo->attrs_used = NULL;
6305 : :
6306 : : /*
6307 : : * If there is a possibility that EvalPlanQual will be executed, we need
6308 : : * to be able to reconstruct the row using scans of the base relations.
6309 : : * GetExistingLocalJoinPath will find a suitable path for this purpose in
6310 : : * the path list of the joinrel, if one exists. We must be careful to
6311 : : * call it before adding any ForeignPath, since the ForeignPath might
6312 : : * dominate the only suitable local path available. We also do it before
6313 : : * calling foreign_join_ok(), since that function updates fpinfo and marks
6314 : : * it as pushable if the join is found to be pushable.
6315 : : */
6316 [ + + ]: 392 : if (root->parse->commandType == CMD_DELETE ||
6317 [ + + ]: 378 : root->parse->commandType == CMD_UPDATE ||
6318 [ + + ]: 352 : root->rowMarks)
6319 : : {
6320 : 76 : epq_path = GetExistingLocalJoinPath(joinrel);
6321 [ - + ]: 76 : if (!epq_path)
6322 : : {
3497 rhaas@postgresql.org 6323 [ # # ]:UBC 0 : elog(DEBUG3, "could not push down foreign join because a local path suitable for EPQ checks was not found");
6324 : 0 : return;
6325 : : }
6326 : : }
6327 : : else
3497 rhaas@postgresql.org 6328 :CBC 316 : epq_path = NULL;
6329 : :
6330 [ + + ]: 392 : if (!foreign_join_ok(root, joinrel, jointype, outerrel, innerrel, extra))
6331 : : {
6332 : : /* Free path required for EPQ if we copied one; we don't need it now */
6333 [ + + ]: 59 : if (epq_path)
6334 : 2 : pfree(epq_path);
6335 : 59 : return;
6336 : : }
6337 : :
6338 : : /*
6339 : : * Compute the selectivity and cost of the local_conds, so we don't have
6340 : : * to do it over again for each path. The best we can do for these
6341 : : * conditions is to estimate selectivity on the basis of local statistics.
6342 : : * The local conditions are applied after the join has been computed on
6343 : : * the remote side like quals in WHERE clause, so pass jointype as
6344 : : * JOIN_INNER.
6345 : : */
6346 : 333 : fpinfo->local_conds_sel = clauselist_selectivity(root,
6347 : : fpinfo->local_conds,
6348 : : 0,
6349 : : JOIN_INNER,
6350 : : NULL);
6351 : 333 : cost_qual_eval(&fpinfo->local_conds_cost, fpinfo->local_conds, root);
6352 : :
6353 : : /*
6354 : : * If we are going to estimate costs locally, estimate the join clause
6355 : : * selectivity here while we have special join info.
6356 : : */
3340 tgl@sss.pgh.pa.us 6357 [ + + ]: 333 : if (!fpinfo->use_remote_estimate)
3497 rhaas@postgresql.org 6358 : 112 : fpinfo->joinclause_sel = clauselist_selectivity(root, fpinfo->joinclauses,
6359 : : 0, fpinfo->jointype,
6360 : : extra->sjinfo);
6361 : :
6362 : : /* Estimate costs for bare join relation */
2349 efujita@postgresql.o 6363 : 333 : estimate_path_cost_size(root, joinrel, NIL, NIL, NULL,
6364 : : &rows, &width, &disabled_nodes,
6365 : : &startup_cost, &total_cost);
6366 : : /* Now update this information in the joinrel */
3497 rhaas@postgresql.org 6367 : 333 : joinrel->rows = rows;
3463 tgl@sss.pgh.pa.us 6368 : 333 : joinrel->reltarget->width = width;
3497 rhaas@postgresql.org 6369 : 333 : fpinfo->rows = rows;
6370 : 333 : fpinfo->width = width;
381 6371 : 333 : fpinfo->disabled_nodes = disabled_nodes;
3497 6372 : 333 : fpinfo->startup_cost = startup_cost;
6373 : 333 : fpinfo->total_cost = total_cost;
6374 : :
6375 : : /*
6376 : : * Create a new join path and add it to the joinrel which represents a
6377 : : * join between foreign tables.
6378 : : */
2403 tgl@sss.pgh.pa.us 6379 : 333 : joinpath = create_foreign_join_path(root,
6380 : : joinrel,
6381 : : NULL, /* default pathtarget */
6382 : : rows,
6383 : : disabled_nodes,
6384 : : startup_cost,
6385 : : total_cost,
6386 : : NIL, /* no pathkeys */
6387 : : joinrel->lateral_relids,
6388 : : epq_path,
6389 : : extra->restrictlist,
6390 : : NIL); /* no fdw_private */
6391 : :
6392 : : /* Add generated path into joinrel by add_path(). */
3497 rhaas@postgresql.org 6393 : 333 : add_path(joinrel, (Path *) joinpath);
6394 : :
6395 : : /* Consider pathkeys for the join relation */
753 efujita@postgresql.o 6396 : 333 : add_paths_with_pathkeys_for_rel(root, joinrel, epq_path,
6397 : : extra->restrictlist);
6398 : :
6399 : : /* XXX Consider parameterized paths for the join relation */
6400 : : }
6401 : :
6402 : : /*
6403 : : * Assess whether the aggregation, grouping and having operations can be pushed
6404 : : * down to the foreign server. As a side effect, save information we obtain in
6405 : : * this function to PgFdwRelationInfo of the input relation.
6406 : : */
6407 : : static bool
2714 rhaas@postgresql.org 6408 : 160 : foreign_grouping_ok(PlannerInfo *root, RelOptInfo *grouped_rel,
6409 : : Node *havingQual)
6410 : : {
3242 6411 : 160 : Query *query = root->parse;
6412 : 160 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) grouped_rel->fdw_private;
2714 6413 : 160 : PathTarget *grouping_target = grouped_rel->reltarget;
6414 : : PgFdwRelationInfo *ofpinfo;
6415 : : ListCell *lc;
6416 : : int i;
3242 6417 : 160 : List *tlist = NIL;
6418 : :
6419 : : /* We currently don't support pushing Grouping Sets. */
6420 [ + + ]: 160 : if (query->groupingSets)
6421 : 6 : return false;
6422 : :
6423 : : /* Get the fpinfo of the underlying scan relation. */
6424 : 154 : ofpinfo = (PgFdwRelationInfo *) fpinfo->outerrel->fdw_private;
6425 : :
6426 : : /*
6427 : : * If underlying scan relation has any local conditions, those conditions
6428 : : * are required to be applied before performing aggregation. Hence the
6429 : : * aggregate cannot be pushed down.
6430 : : */
6431 [ + + ]: 154 : if (ofpinfo->local_conds)
6432 : 9 : return false;
6433 : :
6434 : : /*
6435 : : * Examine grouping expressions, as well as other expressions we'd need to
6436 : : * compute, and check whether they are safe to push down to the foreign
6437 : : * server. All GROUP BY expressions will be part of the grouping target
6438 : : * and thus there is no need to search for them separately. Add grouping
6439 : : * expressions into target list which will be passed to foreign server.
6440 : : *
6441 : : * A tricky fine point is that we must not put any expression into the
6442 : : * target list that is just a foreign param (that is, something that
6443 : : * deparse.c would conclude has to be sent to the foreign server). If we
6444 : : * do, the expression will also appear in the fdw_exprs list of the plan
6445 : : * node, and setrefs.c will get confused and decide that the fdw_exprs
6446 : : * entry is actually a reference to the fdw_scan_tlist entry, resulting in
6447 : : * a broken plan. Somewhat oddly, it's OK if the expression contains such
6448 : : * a node, as long as it's not at top level; then no match is possible.
6449 : : */
6450 : 145 : i = 0;
6451 [ + - + + : 425 : foreach(lc, grouping_target->exprs)
+ + ]
6452 : : {
6453 : 298 : Expr *expr = (Expr *) lfirst(lc);
6454 [ + - ]: 298 : Index sgref = get_pathtarget_sortgroupref(grouping_target, i);
6455 : : ListCell *l;
6456 : :
6457 : : /*
6458 : : * Check whether this expression is part of GROUP BY clause. Note we
6459 : : * check the whole GROUP BY clause not just processed_groupClause,
6460 : : * because we will ship all of it, cf. appendGroupByClause.
6461 : : */
6462 [ + + + + ]: 298 : if (sgref && get_sortgroupref_clause_noerr(sgref, query->groupClause))
6463 : 92 : {
6464 : : TargetEntry *tle;
6465 : :
6466 : : /*
6467 : : * If any GROUP BY expression is not shippable, then we cannot
6468 : : * push down aggregation to the foreign server.
6469 : : */
6470 [ + + ]: 95 : if (!is_foreign_expr(root, grouped_rel, expr))
6471 : 18 : return false;
6472 : :
6473 : : /*
6474 : : * If it would be a foreign param, we can't put it into the tlist,
6475 : : * so we have to fail.
6476 : : */
2324 tgl@sss.pgh.pa.us 6477 [ + + ]: 94 : if (is_foreign_param(root, grouped_rel, expr))
6478 : 2 : return false;
6479 : :
6480 : : /*
6481 : : * Pushable, so add to tlist. We need to create a TLE for this
6482 : : * expression and apply the sortgroupref to it. We cannot use
6483 : : * add_to_flat_tlist() here because that avoids making duplicate
6484 : : * entries in the tlist. If there are duplicate entries with
6485 : : * distinct sortgrouprefs, we have to duplicate that situation in
6486 : : * the output tlist.
6487 : : */
2794 6488 : 92 : tle = makeTargetEntry(expr, list_length(tlist) + 1, NULL, false);
6489 : 92 : tle->ressortgroupref = sgref;
6490 : 92 : tlist = lappend(tlist, tle);
6491 : : }
6492 : : else
6493 : : {
6494 : : /*
6495 : : * Non-grouping expression we need to compute. Can we ship it
6496 : : * as-is to the foreign server?
6497 : : */
2324 6498 [ + + ]: 203 : if (is_foreign_expr(root, grouped_rel, expr) &&
6499 [ + + ]: 182 : !is_foreign_param(root, grouped_rel, expr))
3242 rhaas@postgresql.org 6500 : 180 : {
6501 : : /* Yes, so add to tlist as-is; OK to suppress duplicates */
6502 : 180 : tlist = add_to_flat_tlist(tlist, list_make1(expr));
6503 : : }
6504 : : else
6505 : : {
6506 : : /* Not pushable as a whole; extract its Vars and aggregates */
6507 : : List *aggvars;
6508 : :
6509 : 23 : aggvars = pull_var_clause((Node *) expr,
6510 : : PVC_INCLUDE_AGGREGATES);
6511 : :
6512 : : /*
6513 : : * If any aggregate expression is not shippable, then we
6514 : : * cannot push down aggregation to the foreign server. (We
6515 : : * don't have to check is_foreign_param, since that certainly
6516 : : * won't return true for any such expression.)
6517 : : */
6518 [ + + ]: 23 : if (!is_foreign_expr(root, grouped_rel, (Expr *) aggvars))
6519 : 15 : return false;
6520 : :
6521 : : /*
6522 : : * Add aggregates, if any, into the targetlist. Plain Vars
6523 : : * outside an aggregate can be ignored, because they should be
6524 : : * either same as some GROUP BY column or part of some GROUP
6525 : : * BY expression. In either case, they are already part of
6526 : : * the targetlist and thus no need to add them again. In fact
6527 : : * including plain Vars in the tlist when they do not match a
6528 : : * GROUP BY column would cause the foreign server to complain
6529 : : * that the shipped query is invalid.
6530 : : */
6531 [ + + + + : 14 : foreach(l, aggvars)
+ + ]
6532 : : {
1065 drowley@postgresql.o 6533 : 6 : Expr *aggref = (Expr *) lfirst(l);
6534 : :
6535 [ + + ]: 6 : if (IsA(aggref, Aggref))
6536 : 4 : tlist = add_to_flat_tlist(tlist, list_make1(aggref));
6537 : : }
6538 : : }
6539 : : }
6540 : :
3242 rhaas@postgresql.org 6541 : 280 : i++;
6542 : : }
6543 : :
6544 : : /*
6545 : : * Classify the pushable and non-pushable HAVING clauses and save them in
6546 : : * remote_conds and local_conds of the grouped rel's fpinfo.
6547 : : */
2714 6548 [ + + ]: 127 : if (havingQual)
6549 : : {
6550 [ + - + + : 34 : foreach(lc, (List *) havingQual)
+ + ]
6551 : : {
3242 6552 : 19 : Expr *expr = (Expr *) lfirst(lc);
6553 : : RestrictInfo *rinfo;
6554 : :
6555 : : /*
6556 : : * Currently, the core code doesn't wrap havingQuals in
6557 : : * RestrictInfos, so we must make our own.
6558 : : */
3070 tgl@sss.pgh.pa.us 6559 [ - + ]: 19 : Assert(!IsA(expr, RestrictInfo));
1689 6560 : 19 : rinfo = make_restrictinfo(root,
6561 : : expr,
6562 : : true,
6563 : : false,
6564 : : false,
6565 : : false,
6566 : : root->qual_security_level,
6567 : : grouped_rel->relids,
6568 : : NULL,
6569 : : NULL);
3070 6570 [ + + ]: 19 : if (is_foreign_expr(root, grouped_rel, expr))
6571 : 16 : fpinfo->remote_conds = lappend(fpinfo->remote_conds, rinfo);
6572 : : else
6573 : 3 : fpinfo->local_conds = lappend(fpinfo->local_conds, rinfo);
6574 : : }
6575 : : }
6576 : :
6577 : : /*
6578 : : * If there are any local conditions, pull Vars and aggregates from it and
6579 : : * check whether they are safe to pushdown or not.
6580 : : */
3242 rhaas@postgresql.org 6581 [ + + ]: 127 : if (fpinfo->local_conds)
6582 : : {
3070 tgl@sss.pgh.pa.us 6583 : 3 : List *aggvars = NIL;
6584 : :
6585 [ + - + + : 6 : foreach(lc, fpinfo->local_conds)
+ + ]
6586 : : {
6587 : 3 : RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
6588 : :
6589 : 3 : aggvars = list_concat(aggvars,
6590 : 3 : pull_var_clause((Node *) rinfo->clause,
6591 : : PVC_INCLUDE_AGGREGATES));
6592 : : }
6593 : :
3242 rhaas@postgresql.org 6594 [ + - + + : 7 : foreach(lc, aggvars)
+ + ]
6595 : : {
6596 : 5 : Expr *expr = (Expr *) lfirst(lc);
6597 : :
6598 : : /*
6599 : : * If aggregates within local conditions are not safe to push
6600 : : * down, then we cannot push down the query. Vars are already
6601 : : * part of GROUP BY clause which are checked above, so no need to
6602 : : * access them again here. Again, we need not check
6603 : : * is_foreign_param for a foreign aggregate.
6604 : : */
6605 [ + - ]: 5 : if (IsA(expr, Aggref))
6606 : : {
6607 [ + + ]: 5 : if (!is_foreign_expr(root, grouped_rel, expr))
6608 : 1 : return false;
6609 : :
3070 tgl@sss.pgh.pa.us 6610 : 4 : tlist = add_to_flat_tlist(tlist, list_make1(expr));
6611 : : }
6612 : : }
6613 : : }
6614 : :
6615 : : /* Store generated targetlist */
3242 rhaas@postgresql.org 6616 : 126 : fpinfo->grouped_tlist = tlist;
6617 : :
6618 : : /* Safe to pushdown */
6619 : 126 : fpinfo->pushdown_safe = true;
6620 : :
6621 : : /*
6622 : : * Set # of retrieved rows and cached relation costs to some negative
6623 : : * value, so that we can detect when they are set to some sensible values,
6624 : : * during one (usually the first) of the calls to estimate_path_cost_size.
6625 : : */
2276 efujita@postgresql.o 6626 : 126 : fpinfo->retrieved_rows = -1;
3242 rhaas@postgresql.org 6627 : 126 : fpinfo->rel_startup_cost = -1;
6628 : 126 : fpinfo->rel_total_cost = -1;
6629 : :
6630 : : /*
6631 : : * Set the string describing this grouped relation to be used in EXPLAIN
6632 : : * output of corresponding ForeignScan. Note that the decoration we add
6633 : : * to the base relation name mustn't include any digits, or it'll confuse
6634 : : * postgresExplainForeignScan.
6635 : : */
2105 tgl@sss.pgh.pa.us 6636 : 126 : fpinfo->relation_name = psprintf("Aggregate on (%s)",
6637 : : ofpinfo->relation_name);
6638 : :
3242 rhaas@postgresql.org 6639 : 126 : return true;
6640 : : }
6641 : :
6642 : : /*
6643 : : * postgresGetForeignUpperPaths
6644 : : * Add paths for post-join operations like aggregation, grouping etc. if
6645 : : * corresponding operations are safe to push down.
6646 : : */
6647 : : static void
6648 : 967 : postgresGetForeignUpperPaths(PlannerInfo *root, UpperRelationKind stage,
6649 : : RelOptInfo *input_rel, RelOptInfo *output_rel,
6650 : : void *extra)
6651 : : {
6652 : : PgFdwRelationInfo *fpinfo;
6653 : :
6654 : : /*
6655 : : * If input rel is not safe to pushdown, then simply return as we cannot
6656 : : * perform any post-join operations on the foreign server.
6657 : : */
6658 [ + + ]: 967 : if (!input_rel->fdw_private ||
6659 [ + + ]: 901 : !((PgFdwRelationInfo *) input_rel->fdw_private)->pushdown_safe)
6660 : 122 : return;
6661 : :
6662 : : /* Ignore stages we don't support; and skip any duplicate calls. */
2349 efujita@postgresql.o 6663 [ + + + + ]: 845 : if ((stage != UPPERREL_GROUP_AGG &&
6664 [ + + ]: 535 : stage != UPPERREL_ORDERED &&
6665 : 828 : stage != UPPERREL_FINAL) ||
6666 [ - + ]: 828 : output_rel->fdw_private)
3242 rhaas@postgresql.org 6667 : 17 : return;
6668 : :
6669 : 828 : fpinfo = (PgFdwRelationInfo *) palloc0(sizeof(PgFdwRelationInfo));
6670 : 828 : fpinfo->pushdown_safe = false;
2349 efujita@postgresql.o 6671 : 828 : fpinfo->stage = stage;
3242 rhaas@postgresql.org 6672 : 828 : output_rel->fdw_private = fpinfo;
6673 : :
2349 efujita@postgresql.o 6674 [ + + + - ]: 828 : switch (stage)
6675 : : {
6676 : 160 : case UPPERREL_GROUP_AGG:
6677 : 160 : add_foreign_grouping_paths(root, input_rel, output_rel,
6678 : : (GroupPathExtraData *) extra);
6679 : 160 : break;
6680 : 150 : case UPPERREL_ORDERED:
6681 : 150 : add_foreign_ordered_paths(root, input_rel, output_rel);
6682 : 150 : break;
6683 : 518 : case UPPERREL_FINAL:
6684 : 518 : add_foreign_final_paths(root, input_rel, output_rel,
6685 : : (FinalPathExtraData *) extra);
6686 : 518 : break;
2349 efujita@postgresql.o 6687 :UBC 0 : default:
6688 [ # # ]: 0 : elog(ERROR, "unexpected upper relation: %d", (int) stage);
6689 : : break;
6690 : : }
6691 : : }
6692 : :
6693 : : /*
6694 : : * add_foreign_grouping_paths
6695 : : * Add foreign path for grouping and/or aggregation.
6696 : : *
6697 : : * Given input_rel represents the underlying scan. The paths are added to the
6698 : : * given grouped_rel.
6699 : : */
6700 : : static void
3242 rhaas@postgresql.org 6701 :CBC 160 : add_foreign_grouping_paths(PlannerInfo *root, RelOptInfo *input_rel,
6702 : : RelOptInfo *grouped_rel,
6703 : : GroupPathExtraData *extra)
6704 : : {
6705 : 160 : Query *parse = root->parse;
6706 : 160 : PgFdwRelationInfo *ifpinfo = input_rel->fdw_private;
6707 : 160 : PgFdwRelationInfo *fpinfo = grouped_rel->fdw_private;
6708 : : ForeignPath *grouppath;
6709 : : double rows;
6710 : : int width;
6711 : : int disabled_nodes;
6712 : : Cost startup_cost;
6713 : : Cost total_cost;
6714 : :
6715 : : /* Nothing to be done, if there is no grouping or aggregation required. */
6716 [ + + + - : 160 : if (!parse->groupClause && !parse->groupingSets && !parse->hasAggs &&
- + ]
3242 rhaas@postgresql.org 6717 [ # # ]:UBC 0 : !root->hasHavingQual)
3242 rhaas@postgresql.org 6718 :CBC 34 : return;
6719 : :
2714 6720 [ + + - + ]: 160 : Assert(extra->patype == PARTITIONWISE_AGGREGATE_NONE ||
6721 : : extra->patype == PARTITIONWISE_AGGREGATE_FULL);
6722 : :
6723 : : /* save the input_rel as outerrel in fpinfo */
3242 6724 : 160 : fpinfo->outerrel = input_rel;
6725 : :
6726 : : /*
6727 : : * Copy foreign table, foreign server, user mapping, FDW options etc.
6728 : : * details from the input relation's fpinfo.
6729 : : */
6730 : 160 : fpinfo->table = ifpinfo->table;
6731 : 160 : fpinfo->server = ifpinfo->server;
6732 : 160 : fpinfo->user = ifpinfo->user;
3034 bruce@momjian.us 6733 : 160 : merge_fdw_options(fpinfo, ifpinfo, NULL);
6734 : :
6735 : : /*
6736 : : * Assess if it is safe to push down aggregation and grouping.
6737 : : *
6738 : : * Use HAVING qual from extra. In case of child partition, it will have
6739 : : * translated Vars.
6740 : : */
2714 rhaas@postgresql.org 6741 [ + + ]: 160 : if (!foreign_grouping_ok(root, grouped_rel, extra->havingQual))
3242 6742 : 34 : return;
6743 : :
6744 : : /*
6745 : : * Compute the selectivity and cost of the local_conds, so we don't have
6746 : : * to do it over again for each path. (Currently we create just a single
6747 : : * path here, but in future it would be possible that we build more paths
6748 : : * such as pre-sorted paths as in postgresGetForeignPaths and
6749 : : * postgresGetForeignJoinPaths.) The best we can do for these conditions
6750 : : * is to estimate selectivity on the basis of local statistics.
6751 : : */
2468 efujita@postgresql.o 6752 : 126 : fpinfo->local_conds_sel = clauselist_selectivity(root,
6753 : : fpinfo->local_conds,
6754 : : 0,
6755 : : JOIN_INNER,
6756 : : NULL);
6757 : :
6758 : 126 : cost_qual_eval(&fpinfo->local_conds_cost, fpinfo->local_conds, root);
6759 : :
6760 : : /* Estimate the cost of push down */
2349 6761 : 126 : estimate_path_cost_size(root, grouped_rel, NIL, NIL, NULL,
6762 : : &rows, &width, &disabled_nodes,
6763 : : &startup_cost, &total_cost);
6764 : :
6765 : : /* Now update this information in the fpinfo */
3242 rhaas@postgresql.org 6766 : 126 : fpinfo->rows = rows;
6767 : 126 : fpinfo->width = width;
381 6768 : 126 : fpinfo->disabled_nodes = disabled_nodes;
3242 6769 : 126 : fpinfo->startup_cost = startup_cost;
6770 : 126 : fpinfo->total_cost = total_cost;
6771 : :
6772 : : /* Create and add foreign path to the grouping relation. */
2403 tgl@sss.pgh.pa.us 6773 : 126 : grouppath = create_foreign_upper_path(root,
6774 : : grouped_rel,
6775 : 126 : grouped_rel->reltarget,
6776 : : rows,
6777 : : disabled_nodes,
6778 : : startup_cost,
6779 : : total_cost,
6780 : : NIL, /* no pathkeys */
6781 : : NULL,
6782 : : NIL, /* no fdw_restrictinfo list */
6783 : : NIL); /* no fdw_private */
6784 : :
6785 : : /* Add generated path into grouped_rel by add_path(). */
3242 rhaas@postgresql.org 6786 : 126 : add_path(grouped_rel, (Path *) grouppath);
6787 : : }
6788 : :
6789 : : /*
6790 : : * add_foreign_ordered_paths
6791 : : * Add foreign paths for performing the final sort remotely.
6792 : : *
6793 : : * Given input_rel contains the source-data Paths. The paths are added to the
6794 : : * given ordered_rel.
6795 : : */
6796 : : static void
2349 efujita@postgresql.o 6797 : 150 : add_foreign_ordered_paths(PlannerInfo *root, RelOptInfo *input_rel,
6798 : : RelOptInfo *ordered_rel)
6799 : : {
6800 : 150 : Query *parse = root->parse;
6801 : 150 : PgFdwRelationInfo *ifpinfo = input_rel->fdw_private;
6802 : 150 : PgFdwRelationInfo *fpinfo = ordered_rel->fdw_private;
6803 : : PgFdwPathExtraData *fpextra;
6804 : : double rows;
6805 : : int width;
6806 : : int disabled_nodes;
6807 : : Cost startup_cost;
6808 : : Cost total_cost;
6809 : : List *fdw_private;
6810 : : ForeignPath *ordered_path;
6811 : : ListCell *lc;
6812 : :
6813 : : /* Shouldn't get here unless the query has ORDER BY */
6814 [ - + ]: 150 : Assert(parse->sortClause);
6815 : :
6816 : : /* We don't support cases where there are any SRFs in the targetlist */
6817 [ - + ]: 150 : if (parse->hasTargetSRFs)
6818 : 108 : return;
6819 : :
6820 : : /* Save the input_rel as outerrel in fpinfo */
6821 : 150 : fpinfo->outerrel = input_rel;
6822 : :
6823 : : /*
6824 : : * Copy foreign table, foreign server, user mapping, FDW options etc.
6825 : : * details from the input relation's fpinfo.
6826 : : */
6827 : 150 : fpinfo->table = ifpinfo->table;
6828 : 150 : fpinfo->server = ifpinfo->server;
6829 : 150 : fpinfo->user = ifpinfo->user;
6830 : 150 : merge_fdw_options(fpinfo, ifpinfo, NULL);
6831 : :
6832 : : /*
6833 : : * If the input_rel is a base or join relation, we would already have
6834 : : * considered pushing down the final sort to the remote server when
6835 : : * creating pre-sorted foreign paths for that relation, because the
6836 : : * query_pathkeys is set to the root->sort_pathkeys in that case (see
6837 : : * standard_qp_callback()).
6838 : : */
6839 [ + + ]: 150 : if (input_rel->reloptkind == RELOPT_BASEREL ||
6840 [ + + ]: 109 : input_rel->reloptkind == RELOPT_JOINREL)
6841 : : {
6842 [ - + ]: 104 : Assert(root->query_pathkeys == root->sort_pathkeys);
6843 : :
6844 : : /* Safe to push down if the query_pathkeys is safe to push down */
6845 : 104 : fpinfo->pushdown_safe = ifpinfo->qp_is_pushdown_safe;
6846 : :
6847 : 104 : return;
6848 : : }
6849 : :
6850 : : /* The input_rel should be a grouping relation */
6851 [ + - - + ]: 46 : Assert(input_rel->reloptkind == RELOPT_UPPER_REL &&
6852 : : ifpinfo->stage == UPPERREL_GROUP_AGG);
6853 : :
6854 : : /*
6855 : : * We try to create a path below by extending a simple foreign path for
6856 : : * the underlying grouping relation to perform the final sort remotely,
6857 : : * which is stored into the fdw_private list of the resulting path.
6858 : : */
6859 : :
6860 : : /* Assess if it is safe to push down the final sort */
6861 [ + + + + : 94 : foreach(lc, root->sort_pathkeys)
+ + ]
6862 : : {
6863 : 52 : PathKey *pathkey = (PathKey *) lfirst(lc);
6864 : 52 : EquivalenceClass *pathkey_ec = pathkey->pk_eclass;
6865 : :
6866 : : /*
6867 : : * is_foreign_expr would detect volatile expressions as well, but
6868 : : * checking ec_has_volatile here saves some cycles.
6869 : : */
6870 [ + + ]: 52 : if (pathkey_ec->ec_has_volatile)
6871 : 4 : return;
6872 : :
6873 : : /*
6874 : : * Can't push down the sort if pathkey's opfamily is not shippable.
6875 : : */
1255 tgl@sss.pgh.pa.us 6876 [ - + ]: 48 : if (!is_shippable(pathkey->pk_opfamily, OperatorFamilyRelationId,
6877 : : fpinfo))
1255 tgl@sss.pgh.pa.us 6878 :UBC 0 : return;
6879 : :
6880 : : /*
6881 : : * The EC must contain a shippable EM that is computed in input_rel's
6882 : : * reltarget, else we can't push down the sort.
6883 : : */
1255 tgl@sss.pgh.pa.us 6884 [ - + ]:CBC 48 : if (find_em_for_rel_target(root,
6885 : : pathkey_ec,
6886 : : input_rel) == NULL)
2349 efujita@postgresql.o 6887 :UBC 0 : return;
6888 : : }
6889 : :
6890 : : /* Safe to push down */
2349 efujita@postgresql.o 6891 :CBC 42 : fpinfo->pushdown_safe = true;
6892 : :
6893 : : /* Construct PgFdwPathExtraData */
6894 : 42 : fpextra = (PgFdwPathExtraData *) palloc0(sizeof(PgFdwPathExtraData));
6895 : 42 : fpextra->target = root->upper_targets[UPPERREL_ORDERED];
6896 : 42 : fpextra->has_final_sort = true;
6897 : :
6898 : : /* Estimate the costs of performing the final sort remotely */
6899 : 42 : estimate_path_cost_size(root, input_rel, NIL, root->sort_pathkeys, fpextra,
6900 : : &rows, &width, &disabled_nodes,
6901 : : &startup_cost, &total_cost);
6902 : :
6903 : : /*
6904 : : * Build the fdw_private list that will be used by postgresGetForeignPlan.
6905 : : * Items in the list must match order in enum FdwPathPrivateIndex.
6906 : : */
1331 peter@eisentraut.org 6907 : 42 : fdw_private = list_make2(makeBoolean(true), makeBoolean(false));
6908 : :
6909 : : /* Create foreign ordering path */
2349 efujita@postgresql.o 6910 : 42 : ordered_path = create_foreign_upper_path(root,
6911 : : input_rel,
6912 : 42 : root->upper_targets[UPPERREL_ORDERED],
6913 : : rows,
6914 : : disabled_nodes,
6915 : : startup_cost,
6916 : : total_cost,
6917 : : root->sort_pathkeys,
6918 : : NULL, /* no extra plan */
6919 : : NIL, /* no fdw_restrictinfo
6920 : : * list */
6921 : : fdw_private);
6922 : :
6923 : : /* and add it to the ordered_rel */
6924 : 42 : add_path(ordered_rel, (Path *) ordered_path);
6925 : : }
6926 : :
6927 : : /*
6928 : : * add_foreign_final_paths
6929 : : * Add foreign paths for performing the final processing remotely.
6930 : : *
6931 : : * Given input_rel contains the source-data Paths. The paths are added to the
6932 : : * given final_rel.
6933 : : */
6934 : : static void
6935 : 518 : add_foreign_final_paths(PlannerInfo *root, RelOptInfo *input_rel,
6936 : : RelOptInfo *final_rel,
6937 : : FinalPathExtraData *extra)
6938 : : {
6939 : 518 : Query *parse = root->parse;
6940 : 518 : PgFdwRelationInfo *ifpinfo = (PgFdwRelationInfo *) input_rel->fdw_private;
6941 : 518 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) final_rel->fdw_private;
6942 : 518 : bool has_final_sort = false;
6943 : 518 : List *pathkeys = NIL;
6944 : : PgFdwPathExtraData *fpextra;
6945 : 518 : bool save_use_remote_estimate = false;
6946 : : double rows;
6947 : : int width;
6948 : : int disabled_nodes;
6949 : : Cost startup_cost;
6950 : : Cost total_cost;
6951 : : List *fdw_private;
6952 : : ForeignPath *final_path;
6953 : :
6954 : : /*
6955 : : * Currently, we only support this for SELECT commands
6956 : : */
6957 [ + + ]: 518 : if (parse->commandType != CMD_SELECT)
6958 : 397 : return;
6959 : :
6960 : : /*
6961 : : * No work if there is no FOR UPDATE/SHARE clause and if there is no need
6962 : : * to add a LIMIT node
6963 : : */
6964 [ + + + + ]: 405 : if (!parse->rowMarks && !extra->limit_needed)
6965 : 270 : return;
6966 : :
6967 : : /* We don't support cases where there are any SRFs in the targetlist */
6968 [ - + ]: 135 : if (parse->hasTargetSRFs)
2349 efujita@postgresql.o 6969 :UBC 0 : return;
6970 : :
6971 : : /* Save the input_rel as outerrel in fpinfo */
2349 efujita@postgresql.o 6972 :CBC 135 : fpinfo->outerrel = input_rel;
6973 : :
6974 : : /*
6975 : : * Copy foreign table, foreign server, user mapping, FDW options etc.
6976 : : * details from the input relation's fpinfo.
6977 : : */
6978 : 135 : fpinfo->table = ifpinfo->table;
6979 : 135 : fpinfo->server = ifpinfo->server;
6980 : 135 : fpinfo->user = ifpinfo->user;
6981 : 135 : merge_fdw_options(fpinfo, ifpinfo, NULL);
6982 : :
6983 : : /*
6984 : : * If there is no need to add a LIMIT node, there might be a ForeignPath
6985 : : * in the input_rel's pathlist that implements all behavior of the query.
6986 : : * Note: we would already have accounted for the query's FOR UPDATE/SHARE
6987 : : * (if any) before we get here.
6988 : : */
6989 [ + + ]: 135 : if (!extra->limit_needed)
6990 : : {
6991 : : ListCell *lc;
6992 : :
6993 [ - + ]: 4 : Assert(parse->rowMarks);
6994 : :
6995 : : /*
6996 : : * Grouping and aggregation are not supported with FOR UPDATE/SHARE,
6997 : : * so the input_rel should be a base, join, or ordered relation; and
6998 : : * if it's an ordered relation, its input relation should be a base or
6999 : : * join relation.
7000 : : */
7001 [ - + - - : 4 : Assert(input_rel->reloptkind == RELOPT_BASEREL ||
- - - - -
- - - ]
7002 : : input_rel->reloptkind == RELOPT_JOINREL ||
7003 : : (input_rel->reloptkind == RELOPT_UPPER_REL &&
7004 : : ifpinfo->stage == UPPERREL_ORDERED &&
7005 : : (ifpinfo->outerrel->reloptkind == RELOPT_BASEREL ||
7006 : : ifpinfo->outerrel->reloptkind == RELOPT_JOINREL)));
7007 : :
7008 [ + - + - : 4 : foreach(lc, input_rel->pathlist)
+ - ]
7009 : : {
7010 : 4 : Path *path = (Path *) lfirst(lc);
7011 : :
7012 : : /*
7013 : : * apply_scanjoin_target_to_paths() uses create_projection_path()
7014 : : * to adjust each of its input paths if needed, whereas
7015 : : * create_ordered_paths() uses apply_projection_to_path() to do
7016 : : * that. So the former might have put a ProjectionPath on top of
7017 : : * the ForeignPath; look through ProjectionPath and see if the
7018 : : * path underneath it is ForeignPath.
7019 : : */
7020 [ - + ]: 4 : if (IsA(path, ForeignPath) ||
2349 efujita@postgresql.o 7021 [ # # ]:UBC 0 : (IsA(path, ProjectionPath) &&
7022 [ # # ]: 0 : IsA(((ProjectionPath *) path)->subpath, ForeignPath)))
7023 : : {
7024 : : /*
7025 : : * Create foreign final path; this gets rid of a
7026 : : * no-longer-needed outer plan (if any), which makes the
7027 : : * EXPLAIN output look cleaner
7028 : : */
2349 efujita@postgresql.o 7029 :CBC 4 : final_path = create_foreign_upper_path(root,
7030 : : path->parent,
7031 : : path->pathtarget,
7032 : : path->rows,
7033 : : path->disabled_nodes,
7034 : : path->startup_cost,
7035 : : path->total_cost,
7036 : : path->pathkeys,
7037 : : NULL, /* no extra plan */
7038 : : NIL, /* no fdw_restrictinfo
7039 : : * list */
7040 : : NIL); /* no fdw_private */
7041 : :
7042 : : /* and add it to the final_rel */
7043 : 4 : add_path(final_rel, (Path *) final_path);
7044 : :
7045 : : /* Safe to push down */
7046 : 4 : fpinfo->pushdown_safe = true;
7047 : :
7048 : 4 : return;
7049 : : }
7050 : : }
7051 : :
7052 : : /*
7053 : : * If we get here it means no ForeignPaths; since we would already
7054 : : * have considered pushing down all operations for the query to the
7055 : : * remote server, give up on it.
7056 : : */
2349 efujita@postgresql.o 7057 :UBC 0 : return;
7058 : : }
7059 : :
2349 efujita@postgresql.o 7060 [ - + ]:CBC 131 : Assert(extra->limit_needed);
7061 : :
7062 : : /*
7063 : : * If the input_rel is an ordered relation, replace the input_rel with its
7064 : : * input relation
7065 : : */
7066 [ + + ]: 131 : if (input_rel->reloptkind == RELOPT_UPPER_REL &&
7067 [ + - ]: 74 : ifpinfo->stage == UPPERREL_ORDERED)
7068 : : {
7069 : 74 : input_rel = ifpinfo->outerrel;
7070 : 74 : ifpinfo = (PgFdwRelationInfo *) input_rel->fdw_private;
7071 : 74 : has_final_sort = true;
7072 : 74 : pathkeys = root->sort_pathkeys;
7073 : : }
7074 : :
7075 : : /* The input_rel should be a base, join, or grouping relation */
7076 [ + + + + : 131 : Assert(input_rel->reloptkind == RELOPT_BASEREL ||
+ - - + ]
7077 : : input_rel->reloptkind == RELOPT_JOINREL ||
7078 : : (input_rel->reloptkind == RELOPT_UPPER_REL &&
7079 : : ifpinfo->stage == UPPERREL_GROUP_AGG));
7080 : :
7081 : : /*
7082 : : * We try to create a path below by extending a simple foreign path for
7083 : : * the underlying base, join, or grouping relation to perform the final
7084 : : * sort (if has_final_sort) and the LIMIT restriction remotely, which is
7085 : : * stored into the fdw_private list of the resulting path. (We
7086 : : * re-estimate the costs of sorting the underlying relation, if
7087 : : * has_final_sort.)
7088 : : */
7089 : :
7090 : : /*
7091 : : * Assess if it is safe to push down the LIMIT and OFFSET to the remote
7092 : : * server
7093 : : */
7094 : :
7095 : : /*
7096 : : * If the underlying relation has any local conditions, the LIMIT/OFFSET
7097 : : * cannot be pushed down.
7098 : : */
7099 [ + + ]: 131 : if (ifpinfo->local_conds)
7100 : 8 : return;
7101 : :
7102 : : /*
7103 : : * If the query has FETCH FIRST .. WITH TIES, 1) it must have ORDER BY as
7104 : : * well, which is used to determine which additional rows tie for the last
7105 : : * place in the result set, and 2) ORDER BY must already have been
7106 : : * determined to be safe to push down before we get here. So in that case
7107 : : * the FETCH clause is safe to push down with ORDER BY if the remote
7108 : : * server is v13 or later, but if not, the remote query will fail entirely
7109 : : * for lack of support for it. Since we do not currently have a way to do
7110 : : * a remote-version check (without accessing the remote server), disable
7111 : : * pushing the FETCH clause for now.
7112 : : */
456 7113 [ + + ]: 123 : if (parse->limitOption == LIMIT_OPTION_WITH_TIES)
7114 : 2 : return;
7115 : :
7116 : : /*
7117 : : * Also, the LIMIT/OFFSET cannot be pushed down, if their expressions are
7118 : : * not safe to remote.
7119 : : */
2349 7120 [ + - ]: 121 : if (!is_foreign_expr(root, input_rel, (Expr *) parse->limitOffset) ||
7121 [ - + ]: 121 : !is_foreign_expr(root, input_rel, (Expr *) parse->limitCount))
2349 efujita@postgresql.o 7122 :UBC 0 : return;
7123 : :
7124 : : /* Safe to push down */
2349 efujita@postgresql.o 7125 :CBC 121 : fpinfo->pushdown_safe = true;
7126 : :
7127 : : /* Construct PgFdwPathExtraData */
7128 : 121 : fpextra = (PgFdwPathExtraData *) palloc0(sizeof(PgFdwPathExtraData));
7129 : 121 : fpextra->target = root->upper_targets[UPPERREL_FINAL];
7130 : 121 : fpextra->has_final_sort = has_final_sort;
7131 : 121 : fpextra->has_limit = extra->limit_needed;
7132 : 121 : fpextra->limit_tuples = extra->limit_tuples;
7133 : 121 : fpextra->count_est = extra->count_est;
7134 : 121 : fpextra->offset_est = extra->offset_est;
7135 : :
7136 : : /*
7137 : : * Estimate the costs of performing the final sort and the LIMIT
7138 : : * restriction remotely. If has_final_sort is false, we wouldn't need to
7139 : : * execute EXPLAIN anymore if use_remote_estimate, since the costs can be
7140 : : * roughly estimated using the costs we already have for the underlying
7141 : : * relation, in the same way as when use_remote_estimate is false. Since
7142 : : * it's pretty expensive to execute EXPLAIN, force use_remote_estimate to
7143 : : * false in that case.
7144 : : */
7145 [ + + ]: 121 : if (!fpextra->has_final_sort)
7146 : : {
7147 : 54 : save_use_remote_estimate = ifpinfo->use_remote_estimate;
7148 : 54 : ifpinfo->use_remote_estimate = false;
7149 : : }
7150 : 121 : estimate_path_cost_size(root, input_rel, NIL, pathkeys, fpextra,
7151 : : &rows, &width, &disabled_nodes,
7152 : : &startup_cost, &total_cost);
7153 [ + + ]: 121 : if (!fpextra->has_final_sort)
7154 : 54 : ifpinfo->use_remote_estimate = save_use_remote_estimate;
7155 : :
7156 : : /*
7157 : : * Build the fdw_private list that will be used by postgresGetForeignPlan.
7158 : : * Items in the list must match order in enum FdwPathPrivateIndex.
7159 : : */
1331 peter@eisentraut.org 7160 : 121 : fdw_private = list_make2(makeBoolean(has_final_sort),
7161 : : makeBoolean(extra->limit_needed));
7162 : :
7163 : : /*
7164 : : * Create foreign final path; this gets rid of a no-longer-needed outer
7165 : : * plan (if any), which makes the EXPLAIN output look cleaner
7166 : : */
2349 efujita@postgresql.o 7167 : 121 : final_path = create_foreign_upper_path(root,
7168 : : input_rel,
7169 : 121 : root->upper_targets[UPPERREL_FINAL],
7170 : : rows,
7171 : : disabled_nodes,
7172 : : startup_cost,
7173 : : total_cost,
7174 : : pathkeys,
7175 : : NULL, /* no extra plan */
7176 : : NIL, /* no fdw_restrictinfo list */
7177 : : fdw_private);
7178 : :
7179 : : /* and add it to the final_rel */
7180 : 121 : add_path(final_rel, (Path *) final_path);
7181 : : }
7182 : :
7183 : : /*
7184 : : * postgresIsForeignPathAsyncCapable
7185 : : * Check whether a given ForeignPath node is async-capable.
7186 : : */
7187 : : static bool
1620 7188 : 237 : postgresIsForeignPathAsyncCapable(ForeignPath *path)
7189 : : {
7190 : 237 : RelOptInfo *rel = ((Path *) path)->parent;
7191 : 237 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) rel->fdw_private;
7192 : :
7193 : 237 : return fpinfo->async_capable;
7194 : : }
7195 : :
7196 : : /*
7197 : : * postgresForeignAsyncRequest
7198 : : * Asynchronously request next tuple from a foreign PostgreSQL table.
7199 : : */
7200 : : static void
7201 : 6175 : postgresForeignAsyncRequest(AsyncRequest *areq)
7202 : : {
7203 : 6175 : produce_tuple_asynchronously(areq, true);
7204 : 6175 : }
7205 : :
7206 : : /*
7207 : : * postgresForeignAsyncConfigureWait
7208 : : * Configure a file descriptor event for which we wish to wait.
7209 : : */
7210 : : static void
7211 : 221 : postgresForeignAsyncConfigureWait(AsyncRequest *areq)
7212 : : {
7213 : 221 : ForeignScanState *node = (ForeignScanState *) areq->requestee;
7214 : 221 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
7215 : 221 : AsyncRequest *pendingAreq = fsstate->conn_state->pendingAreq;
7216 : 221 : AppendState *requestor = (AppendState *) areq->requestor;
7217 : 221 : WaitEventSet *set = requestor->as_eventset;
7218 : :
7219 : : /* This should not be called unless callback_pending */
7220 [ - + ]: 221 : Assert(areq->callback_pending);
7221 : :
7222 : : /*
7223 : : * If process_pending_request() has been invoked on the given request
7224 : : * before we get here, we might have some tuples already; in which case
7225 : : * complete the request
7226 : : */
1499 7227 [ + + ]: 221 : if (fsstate->next_tuple < fsstate->num_tuples)
7228 : : {
7229 : 4 : complete_pending_request(areq);
7230 [ + + ]: 4 : if (areq->request_complete)
7231 : 2 : return;
7232 [ - + ]: 2 : Assert(areq->callback_pending);
7233 : : }
7234 : :
7235 : : /* We must have run out of tuples */
7236 [ - + ]: 219 : Assert(fsstate->next_tuple >= fsstate->num_tuples);
7237 : :
7238 : : /* The core code would have registered postmaster death event */
1620 7239 [ - + ]: 219 : Assert(GetNumRegisteredWaitEvents(set) >= 1);
7240 : :
7241 : : /* Begin an asynchronous data fetch if not already done */
7242 [ + + ]: 219 : if (!pendingAreq)
7243 : 4 : fetch_more_data_begin(areq);
7244 [ + + ]: 215 : else if (pendingAreq->requestor != areq->requestor)
7245 : : {
7246 : : /*
7247 : : * This is the case when the in-process request was made by another
7248 : : * Append. Note that it might be useless to process the request made
7249 : : * by that Append, because the query might not need tuples from that
7250 : : * Append anymore; so we avoid processing it to begin a fetch for the
7251 : : * given request if possible. If there are any child subplans of the
7252 : : * same parent that are ready for new requests, skip the given
7253 : : * request. Likewise, if there are any configured events other than
7254 : : * the postmaster death event, skip it. Otherwise, process the
7255 : : * in-process request, then begin a fetch to configure the event
7256 : : * below, because we might otherwise end up with no configured events
7257 : : * other than the postmaster death event.
7258 : : */
1499 7259 [ - + ]: 8 : if (!bms_is_empty(requestor->as_needrequest))
1499 efujita@postgresql.o 7260 :UBC 0 : return;
1620 efujita@postgresql.o 7261 [ + + ]:CBC 8 : if (GetNumRegisteredWaitEvents(set) > 1)
7262 : 6 : return;
7263 : 2 : process_pending_request(pendingAreq);
7264 : 2 : fetch_more_data_begin(areq);
7265 : : }
7266 [ + + ]: 207 : else if (pendingAreq->requestee != areq->requestee)
7267 : : {
7268 : : /*
7269 : : * This is the case when the in-process request was made by the same
7270 : : * parent but for a different child. Since we configure only the
7271 : : * event for the request made for that child, skip the given request.
7272 : : */
7273 : 9 : return;
7274 : : }
7275 : : else
7276 [ - + ]: 198 : Assert(pendingAreq == areq);
7277 : :
7278 : 203 : AddWaitEventToSet(set, WL_SOCKET_READABLE, PQsocket(fsstate->conn),
7279 : : NULL, areq);
7280 : : }
7281 : :
7282 : : /*
7283 : : * postgresForeignAsyncNotify
7284 : : * Fetch some more tuples from a file descriptor that becomes ready,
7285 : : * requesting next tuple.
7286 : : */
7287 : : static void
7288 : 149 : postgresForeignAsyncNotify(AsyncRequest *areq)
7289 : : {
7290 : 149 : ForeignScanState *node = (ForeignScanState *) areq->requestee;
7291 : 149 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
7292 : :
7293 : : /* The core code would have initialized the callback_pending flag */
7294 [ - + ]: 149 : Assert(!areq->callback_pending);
7295 : :
7296 : : /*
7297 : : * If process_pending_request() has been invoked on the given request
7298 : : * before we get here, we might have some tuples already; in which case
7299 : : * produce the next tuple
7300 : : */
1496 7301 [ + + ]: 149 : if (fsstate->next_tuple < fsstate->num_tuples)
7302 : : {
1496 efujita@postgresql.o 7303 :GBC 1 : produce_tuple_asynchronously(areq, true);
7304 : 1 : return;
7305 : : }
7306 : :
7307 : : /* We must have run out of tuples */
1496 efujita@postgresql.o 7308 [ - + ]:CBC 148 : Assert(fsstate->next_tuple >= fsstate->num_tuples);
7309 : :
7310 : : /* The request should be currently in-process */
7311 [ - + ]: 148 : Assert(fsstate->conn_state->pendingAreq == areq);
7312 : :
7313 : : /* On error, report the original query, not the FETCH. */
1620 7314 [ - + ]: 148 : if (!PQconsumeInput(fsstate->conn))
39 tgl@sss.pgh.pa.us 7315 :UNC 0 : pgfdw_report_error(NULL, fsstate->conn, fsstate->query);
7316 : :
1620 efujita@postgresql.o 7317 :CBC 148 : fetch_more_data(node);
7318 : :
7319 : 148 : produce_tuple_asynchronously(areq, true);
7320 : : }
7321 : :
7322 : : /*
7323 : : * Asynchronously produce next tuple from a foreign PostgreSQL table.
7324 : : */
7325 : : static void
7326 : 6328 : produce_tuple_asynchronously(AsyncRequest *areq, bool fetch)
7327 : : {
7328 : 6328 : ForeignScanState *node = (ForeignScanState *) areq->requestee;
7329 : 6328 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
7330 : 6328 : AsyncRequest *pendingAreq = fsstate->conn_state->pendingAreq;
7331 : : TupleTableSlot *result;
7332 : :
7333 : : /* This should not be called if the request is currently in-process */
7334 [ - + ]: 6328 : Assert(areq != pendingAreq);
7335 : :
7336 : : /* Fetch some more tuples, if we've run out */
7337 [ + + ]: 6328 : if (fsstate->next_tuple >= fsstate->num_tuples)
7338 : : {
7339 : : /* No point in another fetch if we already detected EOF, though */
7340 [ + + ]: 189 : if (!fsstate->eof_reached)
7341 : : {
7342 : : /* Mark the request as pending for a callback */
7343 : 129 : ExecAsyncRequestPending(areq);
7344 : : /* Begin another fetch if requested and if no pending request */
7345 [ + - + + ]: 129 : if (fetch && !pendingAreq)
7346 : 124 : fetch_more_data_begin(areq);
7347 : : }
7348 : : else
7349 : : {
7350 : : /* There's nothing more to do; just return a NULL pointer */
7351 : 60 : result = NULL;
7352 : : /* Mark the request as complete */
7353 : 60 : ExecAsyncRequestDone(areq, result);
7354 : : }
7355 : 189 : return;
7356 : : }
7357 : :
7358 : : /* Get a tuple from the ForeignScan node */
1578 7359 : 6139 : result = areq->requestee->ExecProcNodeReal(areq->requestee);
1620 7360 [ + - + + ]: 6139 : if (!TupIsNull(result))
7361 : : {
7362 : : /* Mark the request as complete */
7363 : 6107 : ExecAsyncRequestDone(areq, result);
7364 : 6107 : return;
7365 : : }
7366 : :
7367 : : /* We must have run out of tuples */
7368 [ - + ]: 32 : Assert(fsstate->next_tuple >= fsstate->num_tuples);
7369 : :
7370 : : /* Fetch some more tuples, if we've not detected EOF yet */
7371 [ + - ]: 32 : if (!fsstate->eof_reached)
7372 : : {
7373 : : /* Mark the request as pending for a callback */
7374 : 32 : ExecAsyncRequestPending(areq);
7375 : : /* Begin another fetch if requested and if no pending request */
7376 [ + + + - ]: 32 : if (fetch && !pendingAreq)
7377 : 30 : fetch_more_data_begin(areq);
7378 : : }
7379 : : else
7380 : : {
7381 : : /* There's nothing more to do; just return a NULL pointer */
1620 efujita@postgresql.o 7382 :UBC 0 : result = NULL;
7383 : : /* Mark the request as complete */
7384 : 0 : ExecAsyncRequestDone(areq, result);
7385 : : }
7386 : : }
7387 : :
7388 : : /*
7389 : : * Begin an asynchronous data fetch.
7390 : : *
7391 : : * Note: this function assumes there is no currently-in-progress asynchronous
7392 : : * data fetch.
7393 : : *
7394 : : * Note: fetch_more_data must be called to fetch the result.
7395 : : */
7396 : : static void
1620 efujita@postgresql.o 7397 :CBC 160 : fetch_more_data_begin(AsyncRequest *areq)
7398 : : {
7399 : 160 : ForeignScanState *node = (ForeignScanState *) areq->requestee;
7400 : 160 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
7401 : : char sql[64];
7402 : :
7403 [ - + ]: 160 : Assert(!fsstate->conn_state->pendingAreq);
7404 : :
7405 : : /* Create the cursor synchronously. */
7406 [ + + ]: 160 : if (!fsstate->cursor_exists)
7407 : 68 : create_cursor(node);
7408 : :
7409 : : /* We will send this query, but not wait for the response. */
7410 : 159 : snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
7411 : : fsstate->fetch_size, fsstate->cursor_number);
7412 : :
1143 fujii@postgresql.org 7413 [ - + ]: 159 : if (!PQsendQuery(fsstate->conn, sql))
39 tgl@sss.pgh.pa.us 7414 :UNC 0 : pgfdw_report_error(NULL, fsstate->conn, fsstate->query);
7415 : :
7416 : : /* Remember that the request is in process */
1620 efujita@postgresql.o 7417 :CBC 159 : fsstate->conn_state->pendingAreq = areq;
7418 : 159 : }
7419 : :
7420 : : /*
7421 : : * Process a pending asynchronous request.
7422 : : */
7423 : : void
7424 : 9 : process_pending_request(AsyncRequest *areq)
7425 : : {
7426 : 9 : ForeignScanState *node = (ForeignScanState *) areq->requestee;
1376 dgustafsson@postgres 7427 : 9 : PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
7428 : :
7429 : : /* The request would have been pending for a callback */
1499 efujita@postgresql.o 7430 [ - + ]: 9 : Assert(areq->callback_pending);
7431 : :
7432 : : /* The request should be currently in-process */
1620 7433 [ - + ]: 9 : Assert(fsstate->conn_state->pendingAreq == areq);
7434 : :
1499 7435 : 9 : fetch_more_data(node);
7436 : :
7437 : : /*
7438 : : * If we didn't get any tuples, must be end of data; complete the request
7439 : : * now. Otherwise, we postpone completing the request until we are called
7440 : : * from postgresForeignAsyncConfigureWait()/postgresForeignAsyncNotify().
7441 : : */
7442 [ - + ]: 9 : if (fsstate->next_tuple >= fsstate->num_tuples)
7443 : : {
7444 : : /* Unlike AsyncNotify, we unset callback_pending ourselves */
1499 efujita@postgresql.o 7445 :UBC 0 : areq->callback_pending = false;
7446 : : /* Mark the request as complete */
7447 : 0 : ExecAsyncRequestDone(areq, NULL);
7448 : : /* Unlike AsyncNotify, we call ExecAsyncResponse ourselves */
7449 : 0 : ExecAsyncResponse(areq);
7450 : : }
1499 efujita@postgresql.o 7451 :CBC 9 : }
7452 : :
7453 : : /*
7454 : : * Complete a pending asynchronous request.
7455 : : */
7456 : : static void
7457 : 4 : complete_pending_request(AsyncRequest *areq)
7458 : : {
7459 : : /* The request would have been pending for a callback */
1620 7460 [ - + ]: 4 : Assert(areq->callback_pending);
7461 : :
7462 : : /* Unlike AsyncNotify, we unset callback_pending ourselves */
7463 : 4 : areq->callback_pending = false;
7464 : :
7465 : : /* We begin a fetch afterwards if necessary; don't fetch */
7466 : 4 : produce_tuple_asynchronously(areq, false);
7467 : :
7468 : : /* Unlike AsyncNotify, we call ExecAsyncResponse ourselves */
7469 : 4 : ExecAsyncResponse(areq);
7470 : :
7471 : : /* Also, we do instrumentation ourselves, if required */
1578 7472 [ + + ]: 4 : if (areq->requestee->instrument)
7473 : 1 : InstrUpdateTupleCount(areq->requestee->instrument,
7474 [ + - - + ]: 1 : TupIsNull(areq->result) ? 0.0 : 1.0);
1620 7475 : 4 : }
7476 : :
7477 : : /*
7478 : : * Create a tuple from the specified row of the PGresult.
7479 : : *
7480 : : * rel is the local representation of the foreign table, attinmeta is
7481 : : * conversion data for the rel's tupdesc, and retrieved_attrs is an
7482 : : * integer list of the table column numbers present in the PGresult.
7483 : : * fsstate is the ForeignScan plan node's execution state.
7484 : : * temp_context is a working context that can be reset after each tuple.
7485 : : *
7486 : : * Note: either rel or fsstate, but not both, can be NULL. rel is NULL
7487 : : * if we're processing a remote join, while fsstate is NULL in a non-query
7488 : : * context such as ANALYZE, or if we're processing a non-scan query node.
7489 : : */
7490 : : static HeapTuple
4580 tgl@sss.pgh.pa.us 7491 : 94400 : make_tuple_from_result_row(PGresult *res,
7492 : : int row,
7493 : : Relation rel,
7494 : : AttInMetadata *attinmeta,
7495 : : List *retrieved_attrs,
7496 : : ForeignScanState *fsstate,
7497 : : MemoryContext temp_context)
7498 : : {
7499 : : HeapTuple tuple;
7500 : : TupleDesc tupdesc;
7501 : : Datum *values;
7502 : : bool *nulls;
4563 7503 : 94400 : ItemPointer ctid = NULL;
7504 : : ConversionLocation errpos;
7505 : : ErrorContextCallback errcallback;
7506 : : MemoryContext oldcontext;
7507 : : ListCell *lc;
7508 : : int j;
7509 : :
4580 7510 [ - + ]: 94400 : Assert(row < PQntuples(res));
7511 : :
7512 : : /*
7513 : : * Do the following work in a temp context that we reset after each tuple.
7514 : : * This cleans up not only the data we have direct access to, but any
7515 : : * cruft the I/O functions might leak.
7516 : : */
7517 : 94400 : oldcontext = MemoryContextSwitchTo(temp_context);
7518 : :
7519 : : /*
7520 : : * Get the tuple descriptor for the row. Use the rel's tupdesc if rel is
7521 : : * provided, otherwise look to the scan node's ScanTupleSlot.
7522 : : */
3497 rhaas@postgresql.org 7523 [ + + ]: 94400 : if (rel)
7524 : 58451 : tupdesc = RelationGetDescr(rel);
7525 : : else
7526 : : {
7527 [ - + ]: 35949 : Assert(fsstate);
2768 7528 : 35949 : tupdesc = fsstate->ss.ss_ScanTupleSlot->tts_tupleDescriptor;
7529 : : }
7530 : :
4551 tgl@sss.pgh.pa.us 7531 : 94400 : values = (Datum *) palloc0(tupdesc->natts * sizeof(Datum));
4580 7532 : 94400 : nulls = (bool *) palloc(tupdesc->natts * sizeof(bool));
7533 : : /* Initialize to nulls for any columns not present in result */
4551 7534 : 94400 : memset(nulls, true, tupdesc->natts * sizeof(bool));
7535 : :
7536 : : /*
7537 : : * Set up and install callback to report where conversion error occurs.
7538 : : */
4580 7539 : 94400 : errpos.cur_attno = 0;
1431 7540 : 94400 : errpos.rel = rel;
3497 rhaas@postgresql.org 7541 : 94400 : errpos.fsstate = fsstate;
4580 tgl@sss.pgh.pa.us 7542 : 94400 : errcallback.callback = conversion_error_callback;
282 peter@eisentraut.org 7543 : 94400 : errcallback.arg = &errpos;
4580 tgl@sss.pgh.pa.us 7544 : 94400 : errcallback.previous = error_context_stack;
7545 : 94400 : error_context_stack = &errcallback;
7546 : :
7547 : : /*
7548 : : * i indexes columns in the relation, j indexes columns in the PGresult.
7549 : : */
4551 7550 : 94400 : j = 0;
7551 [ + + + + : 353993 : foreach(lc, retrieved_attrs)
+ + ]
7552 : : {
7553 : 259598 : int i = lfirst_int(lc);
7554 : : char *valstr;
7555 : :
7556 : : /* fetch next column's textual value */
4580 7557 [ + + ]: 259598 : if (PQgetisnull(res, row, j))
7558 : 10753 : valstr = NULL;
7559 : : else
7560 : 248845 : valstr = PQgetvalue(res, row, j);
7561 : :
7562 : : /*
7563 : : * convert value to internal representation
7564 : : *
7565 : : * Note: we ignore system columns other than ctid and oid in result
7566 : : */
3462 rhaas@postgresql.org 7567 : 259598 : errpos.cur_attno = i;
4551 tgl@sss.pgh.pa.us 7568 [ + + ]: 259598 : if (i > 0)
7569 : : {
7570 : : /* ordinary column */
7571 [ - + ]: 256481 : Assert(i <= tupdesc->natts);
7572 : 256481 : nulls[i - 1] = (valstr == NULL);
7573 : : /* Apply the input function even to nulls, to support domains */
7574 : 256476 : values[i - 1] = InputFunctionCall(&attinmeta->attinfuncs[i - 1],
7575 : : valstr,
7576 : 256481 : attinmeta->attioparams[i - 1],
7577 : 256481 : attinmeta->atttypmods[i - 1]);
7578 : : }
7579 [ + - ]: 3117 : else if (i == SelfItemPointerAttributeNumber)
7580 : : {
7581 : : /* ctid */
7582 [ + - ]: 3117 : if (valstr != NULL)
7583 : : {
7584 : : Datum datum;
7585 : :
7586 : 3117 : datum = DirectFunctionCall1(tidin, CStringGetDatum(valstr));
7587 : 3117 : ctid = (ItemPointer) DatumGetPointer(datum);
7588 : : }
7589 : : }
3462 rhaas@postgresql.org 7590 : 259593 : errpos.cur_attno = 0;
7591 : :
4563 tgl@sss.pgh.pa.us 7592 : 259593 : j++;
7593 : : }
7594 : :
7595 : : /* Uninstall error context callback. */
4580 7596 : 94395 : error_context_stack = errcallback.previous;
7597 : :
7598 : : /*
7599 : : * Check we got the expected number of columns. Note: j == 0 and
7600 : : * PQnfields == 1 is expected, since deparse emits a NULL if no columns.
7601 : : */
4551 7602 [ + + - + ]: 94395 : if (j > 0 && j != PQnfields(res))
4580 tgl@sss.pgh.pa.us 7603 [ # # ]:UBC 0 : elog(ERROR, "remote query result does not match the foreign table");
7604 : :
7605 : : /*
7606 : : * Build the result tuple in caller's memory context.
7607 : : */
4580 tgl@sss.pgh.pa.us 7608 :CBC 94395 : MemoryContextSwitchTo(oldcontext);
7609 : :
7610 : 94395 : tuple = heap_form_tuple(tupdesc, values, nulls);
7611 : :
7612 : : /*
7613 : : * If we have a CTID to return, install it in both t_self and t_ctid.
7614 : : * t_self is the normal place, but if the tuple is converted to a
7615 : : * composite Datum, t_self will be lost; setting t_ctid allows CTID to be
7616 : : * preserved during EvalPlanQual re-evaluations (see ROW_MARK_COPY code).
7617 : : */
4563 7618 [ + + ]: 94395 : if (ctid)
3769 7619 : 3117 : tuple->t_self = tuple->t_data->t_ctid = *ctid;
7620 : :
7621 : : /*
7622 : : * Stomp on the xmin, xmax, and cmin fields from the tuple created by
7623 : : * heap_form_tuple. heap_form_tuple actually creates the tuple with
7624 : : * DatumTupleFields, not HeapTupleFields, but the executor expects
7625 : : * HeapTupleFields and will happily extract system columns on that
7626 : : * assumption. If we don't do this then, for example, the tuple length
7627 : : * ends up in the xmin field, which isn't what we want.
7628 : : */
3431 rhaas@postgresql.org 7629 : 94395 : HeapTupleHeaderSetXmax(tuple->t_data, InvalidTransactionId);
7630 : 94395 : HeapTupleHeaderSetXmin(tuple->t_data, InvalidTransactionId);
7631 : 94395 : HeapTupleHeaderSetCmin(tuple->t_data, InvalidTransactionId);
7632 : :
7633 : : /* Clean up */
4580 tgl@sss.pgh.pa.us 7634 : 94395 : MemoryContextReset(temp_context);
7635 : :
7636 : 94395 : return tuple;
7637 : : }
7638 : :
7639 : : /*
7640 : : * Callback function which is called when error occurs during column value
7641 : : * conversion. Print names of column and relation.
7642 : : *
7643 : : * Note that this function mustn't do any catalog lookups, since we are in
7644 : : * an already-failed transaction. Fortunately, we can get the needed info
7645 : : * from the relation or the query's rangetable instead.
7646 : : */
7647 : : static void
7648 : 5 : conversion_error_callback(void *arg)
7649 : : {
1523 7650 : 5 : ConversionLocation *errpos = (ConversionLocation *) arg;
1431 7651 : 5 : Relation rel = errpos->rel;
1523 7652 : 5 : ForeignScanState *fsstate = errpos->fsstate;
3497 rhaas@postgresql.org 7653 : 5 : const char *attname = NULL;
7654 : 5 : const char *relname = NULL;
3354 7655 : 5 : bool is_wholerow = false;
7656 : :
7657 : : /*
7658 : : * If we're in a scan node, always use aliases from the rangetable, for
7659 : : * consistency between the simple-relation and remote-join cases. Look at
7660 : : * the relation's tupdesc only if we're not in a scan node.
7661 : : */
1431 tgl@sss.pgh.pa.us 7662 [ + + ]: 5 : if (fsstate)
7663 : : {
7664 : : /* ForeignScan case */
7665 : 4 : ForeignScan *fsplan = castNode(ForeignScan, fsstate->ss.ps.plan);
7666 : 4 : int varno = 0;
7667 : 4 : AttrNumber colno = 0;
7668 : :
7669 [ + + ]: 4 : if (fsplan->scan.scanrelid > 0)
7670 : : {
7671 : : /* error occurred in a scan against a foreign table */
7672 : 1 : varno = fsplan->scan.scanrelid;
7673 : 1 : colno = errpos->cur_attno;
7674 : : }
7675 : : else
7676 : : {
7677 : : /* error occurred in a scan against a foreign join */
7678 : : TargetEntry *tle;
7679 : :
7680 : 3 : tle = list_nth_node(TargetEntry, fsplan->fdw_scan_tlist,
7681 : : errpos->cur_attno - 1);
7682 : :
7683 : : /*
7684 : : * Target list can have Vars and expressions. For Vars, we can
7685 : : * get some information, however for expressions we can't. Thus
7686 : : * for expressions, just show generic context message.
7687 : : */
7688 [ + + ]: 3 : if (IsA(tle->expr, Var))
7689 : : {
7690 : 2 : Var *var = (Var *) tle->expr;
7691 : :
7692 : 2 : varno = var->varno;
7693 : 2 : colno = var->varattno;
7694 : : }
7695 : : }
7696 : :
7697 [ + + ]: 4 : if (varno > 0)
7698 : : {
7699 : 3 : EState *estate = fsstate->ss.ps.state;
7700 : 3 : RangeTblEntry *rte = exec_rt_fetch(varno, estate);
7701 : :
7702 : 3 : relname = rte->eref->aliasname;
7703 : :
7704 [ + + ]: 3 : if (colno == 0)
7705 : 1 : is_wholerow = true;
7706 [ + - + - ]: 2 : else if (colno > 0 && colno <= list_length(rte->eref->colnames))
7707 : 2 : attname = strVal(list_nth(rte->eref->colnames, colno - 1));
1431 tgl@sss.pgh.pa.us 7708 [ # # ]:UBC 0 : else if (colno == SelfItemPointerAttributeNumber)
7709 : 0 : attname = "ctid";
7710 : : }
7711 : : }
1431 tgl@sss.pgh.pa.us 7712 [ + - ]:CBC 1 : else if (rel)
7713 : : {
7714 : : /* Non-ForeignScan case (we should always have a rel here) */
7715 : 1 : TupleDesc tupdesc = RelationGetDescr(rel);
7716 : :
7717 : 1 : relname = RelationGetRelationName(rel);
7718 [ + - + - ]: 1 : if (errpos->cur_attno > 0 && errpos->cur_attno <= tupdesc->natts)
7719 : 1 : {
7720 : 1 : Form_pg_attribute attr = TupleDescAttr(tupdesc,
7721 : 1 : errpos->cur_attno - 1);
7722 : :
7723 : 1 : attname = NameStr(attr->attname);
7724 : : }
1431 tgl@sss.pgh.pa.us 7725 [ # # ]:UBC 0 : else if (errpos->cur_attno == SelfItemPointerAttributeNumber)
1523 7726 : 0 : attname = "ctid";
7727 : : }
7728 : :
1523 tgl@sss.pgh.pa.us 7729 [ + + + + ]:CBC 5 : if (relname && is_wholerow)
7730 : 1 : errcontext("whole-row reference to foreign table \"%s\"", relname);
7731 [ + + + - ]: 4 : else if (relname && attname)
7732 : 3 : errcontext("column \"%s\" of foreign table \"%s\"", attname, relname);
7733 : : else
7734 : 1 : errcontext("processing expression at position %d in select list",
7735 : 1 : errpos->cur_attno);
4580 7736 : 5 : }
7737 : :
7738 : : /*
7739 : : * Given an EquivalenceClass and a foreign relation, find an EC member
7740 : : * that can be used to sort the relation remotely according to a pathkey
7741 : : * using this EC.
7742 : : *
7743 : : * If there is more than one suitable candidate, return an arbitrary
7744 : : * one of them. If there is none, return NULL.
7745 : : *
7746 : : * This checks that the EC member expression uses only Vars from the given
7747 : : * rel and is shippable. Caller must separately verify that the pathkey's
7748 : : * ordering operator is shippable.
7749 : : */
7750 : : EquivalenceMember *
1255 7751 : 1800 : find_em_for_rel(PlannerInfo *root, EquivalenceClass *ec, RelOptInfo *rel)
7752 : : {
641 akorotkov@postgresql 7753 : 1800 : PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) rel->fdw_private;
7754 : : EquivalenceMemberIterator it;
7755 : : EquivalenceMember *em;
7756 : :
151 drowley@postgresql.o 7757 : 1800 : setup_eclass_member_iterator(&it, ec, rel->relids);
7758 [ + + ]: 3005 : while ((em = eclass_member_iterator_next(&it)) != NULL)
7759 : : {
7760 : : /*
7761 : : * Note we require !bms_is_empty, else we'd accept constant
7762 : : * expressions which are not suitable for the purpose.
7763 : : */
1255 tgl@sss.pgh.pa.us 7764 [ + + ]: 2725 : if (bms_is_subset(em->em_relids, rel->relids) &&
7765 [ + + + + ]: 3097 : !bms_is_empty(em->em_relids) &&
641 akorotkov@postgresql 7766 [ + + ]: 3084 : bms_is_empty(bms_intersect(em->em_relids, fpinfo->hidden_subquery_rels)) &&
1255 tgl@sss.pgh.pa.us 7767 : 1536 : is_foreign_expr(root, rel, em->em_expr))
7768 : 1520 : return em;
7769 : : }
7770 : :
7771 : 280 : return NULL;
7772 : : }
7773 : :
7774 : : /*
7775 : : * Find an EquivalenceClass member that is to be computed as a sort column
7776 : : * in the given rel's reltarget, and is shippable.
7777 : : *
7778 : : * If there is more than one suitable candidate, return an arbitrary
7779 : : * one of them. If there is none, return NULL.
7780 : : *
7781 : : * This checks that the EC member expression uses only Vars from the given
7782 : : * rel and is shippable. Caller must separately verify that the pathkey's
7783 : : * ordering operator is shippable.
7784 : : */
7785 : : EquivalenceMember *
7786 : 255 : find_em_for_rel_target(PlannerInfo *root, EquivalenceClass *ec,
7787 : : RelOptInfo *rel)
7788 : : {
7789 : 255 : PathTarget *target = rel->reltarget;
7790 : : ListCell *lc1;
7791 : : int i;
7792 : :
2349 efujita@postgresql.o 7793 : 255 : i = 0;
7794 [ + - + - : 425 : foreach(lc1, target->exprs)
+ - ]
7795 : : {
7796 : 425 : Expr *expr = (Expr *) lfirst(lc1);
7797 [ + - ]: 425 : Index sgref = get_pathtarget_sortgroupref(target, i);
7798 : : ListCell *lc2;
7799 : :
7800 : : /* Ignore non-sort expressions */
7801 [ + + + + ]: 765 : if (sgref == 0 ||
7802 : 340 : get_sortgroupref_clause_noerr(sgref,
7803 : 340 : root->parse->sortClause) == NULL)
7804 : : {
7805 : 93 : i++;
7806 : 93 : continue;
7807 : : }
7808 : :
7809 : : /* We ignore binary-compatible relabeling on both ends */
7810 [ + - - + ]: 332 : while (expr && IsA(expr, RelabelType))
2349 efujita@postgresql.o 7811 :UBC 0 : expr = ((RelabelType *) expr)->arg;
7812 : :
7813 : : /*
7814 : : * Locate an EquivalenceClass member matching this expr, if any.
7815 : : * Ignore child members.
7816 : : */
2349 efujita@postgresql.o 7817 [ + - + + :CBC 413 : foreach(lc2, ec->ec_members)
+ + ]
7818 : : {
7819 : 336 : EquivalenceMember *em = (EquivalenceMember *) lfirst(lc2);
7820 : : Expr *em_expr;
7821 : :
7822 : : /* Don't match constants */
7823 [ - + ]: 336 : if (em->em_is_const)
2349 efujita@postgresql.o 7824 :UBC 0 : continue;
7825 : :
7826 : : /* Child members should not exist in ec_members */
151 drowley@postgresql.o 7827 [ - + ]:CBC 336 : Assert(!em->em_is_child);
7828 : :
7829 : : /* Match if same expression (after stripping relabel) */
2349 efujita@postgresql.o 7830 : 336 : em_expr = em->em_expr;
7831 [ + - + + ]: 348 : while (em_expr && IsA(em_expr, RelabelType))
7832 : 12 : em_expr = ((RelabelType *) em_expr)->arg;
7833 : :
1255 tgl@sss.pgh.pa.us 7834 [ + + ]: 336 : if (!equal(em_expr, expr))
7835 : 81 : continue;
7836 : :
7837 : : /* Check that expression (including relabels!) is shippable */
7838 [ + - ]: 255 : if (is_foreign_expr(root, rel, em->em_expr))
7839 : 255 : return em;
7840 : : }
7841 : :
2349 efujita@postgresql.o 7842 : 77 : i++;
7843 : : }
7844 : :
1255 tgl@sss.pgh.pa.us 7845 :UBC 0 : return NULL;
7846 : : }
7847 : :
7848 : : /*
7849 : : * Determine batch size for a given foreign table. The option specified for
7850 : : * a table has precedence.
7851 : : */
7852 : : static int
1690 tomas.vondra@postgre 7853 :CBC 146 : get_batch_size_option(Relation rel)
7854 : : {
1578 tgl@sss.pgh.pa.us 7855 : 146 : Oid foreigntableid = RelationGetRelid(rel);
7856 : : ForeignTable *table;
7857 : : ForeignServer *server;
7858 : : List *options;
7859 : : ListCell *lc;
7860 : :
7861 : : /* we use 1 by default, which means "no batching" */
7862 : 146 : int batch_size = 1;
7863 : :
7864 : : /*
7865 : : * Load options for table and server. We append server options after table
7866 : : * options, because table options take precedence.
7867 : : */
1690 tomas.vondra@postgre 7868 : 146 : table = GetForeignTable(foreigntableid);
7869 : 146 : server = GetForeignServer(table->serverid);
7870 : :
7871 : 146 : options = NIL;
7872 : 146 : options = list_concat(options, table->options);
7873 : 146 : options = list_concat(options, server->options);
7874 : :
7875 : : /* See if either table or server specifies batch_size. */
7876 [ + - + + : 766 : foreach(lc, options)
+ + ]
7877 : : {
7878 : 655 : DefElem *def = (DefElem *) lfirst(lc);
7879 : :
7880 [ + + ]: 655 : if (strcmp(def->defname, "batch_size") == 0)
7881 : : {
1522 fujii@postgresql.org 7882 : 35 : (void) parse_int(defGetString(def), &batch_size, 0, NULL);
1690 tomas.vondra@postgre 7883 : 35 : break;
7884 : : }
7885 : : }
7886 : :
7887 : 146 : return batch_size;
7888 : : }
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