Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * tuptable.h
4 : : * tuple table support stuff
5 : : *
6 : : *
7 : : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
8 : : * Portions Copyright (c) 1994, Regents of the University of California
9 : : *
10 : : * src/include/executor/tuptable.h
11 : : *
12 : : *-------------------------------------------------------------------------
13 : : */
14 : : #ifndef TUPTABLE_H
15 : : #define TUPTABLE_H
16 : :
17 : : #include "access/htup.h"
18 : : #include "access/htup_details.h"
19 : : #include "access/sysattr.h"
20 : : #include "access/tupdesc.h"
21 : : #include "storage/buf.h"
22 : :
23 : : /*----------
24 : : * The executor stores tuples in a "tuple table" which is a List of
25 : : * independent TupleTableSlots.
26 : : *
27 : : * There's various different types of tuple table slots, each being able to
28 : : * store different types of tuples. Additional types of slots can be added
29 : : * without modifying core code. The type of a slot is determined by the
30 : : * TupleTableSlotOps* passed to the slot creation routine. The builtin types
31 : : * of slots are
32 : : *
33 : : * 1. physical tuple in a disk buffer page (TTSOpsBufferHeapTuple)
34 : : * 2. physical tuple constructed in palloc'ed memory (TTSOpsHeapTuple)
35 : : * 3. "minimal" physical tuple constructed in palloc'ed memory
36 : : * (TTSOpsMinimalTuple)
37 : : * 4. "virtual" tuple consisting of Datum/isnull arrays (TTSOpsVirtual)
38 : : *
39 : : *
40 : : * The first two cases are similar in that they both deal with "materialized"
41 : : * tuples, but resource management is different. For a tuple in a disk page
42 : : * we need to hold a pin on the buffer until the TupleTableSlot's reference
43 : : * to the tuple is dropped; while for a palloc'd tuple we usually want the
44 : : * tuple pfree'd when the TupleTableSlot's reference is dropped.
45 : : *
46 : : * A "minimal" tuple is handled similarly to a palloc'd regular tuple.
47 : : * At present, minimal tuples never are stored in buffers, so there is no
48 : : * parallel to case 1. Note that a minimal tuple has no "system columns".
49 : : *
50 : : * A "virtual" tuple is an optimization used to minimize physical data copying
51 : : * in a nest of plan nodes. Until materialized pass-by-reference Datums in
52 : : * the slot point to storage that is not directly associated with the
53 : : * TupleTableSlot; generally they will point to part of a tuple stored in a
54 : : * lower plan node's output TupleTableSlot, or to a function result
55 : : * constructed in a plan node's per-tuple econtext. It is the responsibility
56 : : * of the generating plan node to be sure these resources are not released for
57 : : * as long as the virtual tuple needs to be valid or is materialized. Note
58 : : * also that a virtual tuple does not have any "system columns".
59 : : *
60 : : * The Datum/isnull arrays of a TupleTableSlot serve double duty. For virtual
61 : : * slots they are the authoritative data. For the other builtin slots,
62 : : * the arrays contain data extracted from the tuple. (In this state, any
63 : : * pass-by-reference Datums point into the physical tuple.) The extracted
64 : : * information is built "lazily", ie, only as needed. This serves to avoid
65 : : * repeated extraction of data from the physical tuple.
66 : : *
67 : : * A TupleTableSlot can also be "empty", indicated by flag TTS_FLAG_EMPTY set
68 : : * in tts_flags, holding no valid data. This is the only valid state for a
69 : : * freshly-created slot that has not yet had a tuple descriptor assigned to
70 : : * it. In this state, TTS_FLAG_SHOULDFREE should not be set in tts_flags and
71 : : * tts_nvalid should be set to zero.
72 : : *
73 : : * The tupleDescriptor is simply referenced, not copied, by the TupleTableSlot
74 : : * code. The caller of ExecSetSlotDescriptor() is responsible for providing
75 : : * a descriptor that will live as long as the slot does. (Typically, both
76 : : * slots and descriptors are in per-query memory and are freed by memory
77 : : * context deallocation at query end; so it's not worth providing any extra
78 : : * mechanism to do more. However, the slot will increment the tupdesc
79 : : * reference count if a reference-counted tupdesc is supplied.)
80 : : *
81 : : * When TTS_FLAG_SHOULDFREE is set in tts_flags, the physical tuple is "owned"
82 : : * by the slot and should be freed when the slot's reference to the tuple is
83 : : * dropped.
84 : : *
85 : : * tts_values/tts_isnull are allocated either when the slot is created (when
86 : : * the descriptor is provided), or when a descriptor is assigned to the slot;
87 : : * they are of length equal to the descriptor's natts.
88 : : *
89 : : * The TTS_FLAG_SLOW flag is saved state for
90 : : * slot_deform_heap_tuple, and should not be touched by any other code.
91 : : *----------
92 : : */
93 : :
94 : : /* true = slot is empty */
95 : : #define TTS_FLAG_EMPTY (1 << 1)
96 : : #define TTS_EMPTY(slot) (((slot)->tts_flags & TTS_FLAG_EMPTY) != 0)
97 : :
98 : : /* should pfree tuple "owned" by the slot? */
99 : : #define TTS_FLAG_SHOULDFREE (1 << 2)
100 : : #define TTS_SHOULDFREE(slot) (((slot)->tts_flags & TTS_FLAG_SHOULDFREE) != 0)
101 : :
102 : : /* saved state for slot_deform_heap_tuple */
103 : : #define TTS_FLAG_SLOW (1 << 3)
104 : : #define TTS_SLOW(slot) (((slot)->tts_flags & TTS_FLAG_SLOW) != 0)
105 : :
106 : : /* fixed tuple descriptor */
107 : : #define TTS_FLAG_FIXED (1 << 4)
108 : : #define TTS_FIXED(slot) (((slot)->tts_flags & TTS_FLAG_FIXED) != 0)
109 : :
110 : : struct TupleTableSlotOps;
111 : : typedef struct TupleTableSlotOps TupleTableSlotOps;
112 : :
113 : : /* base tuple table slot type */
114 : : typedef struct TupleTableSlot
115 : : {
116 : : NodeTag type;
117 : : #define FIELDNO_TUPLETABLESLOT_FLAGS 1
118 : : uint16 tts_flags; /* Boolean states */
119 : : #define FIELDNO_TUPLETABLESLOT_NVALID 2
120 : : AttrNumber tts_nvalid; /* # of valid values in tts_values */
121 : : const TupleTableSlotOps *const tts_ops; /* implementation of slot */
122 : : #define FIELDNO_TUPLETABLESLOT_TUPLEDESCRIPTOR 4
123 : : TupleDesc tts_tupleDescriptor; /* slot's tuple descriptor */
124 : : #define FIELDNO_TUPLETABLESLOT_VALUES 5
125 : : Datum *tts_values; /* current per-attribute values */
126 : : #define FIELDNO_TUPLETABLESLOT_ISNULL 6
127 : : bool *tts_isnull; /* current per-attribute isnull flags */
128 : : MemoryContext tts_mcxt; /* slot itself is in this context */
129 : : ItemPointerData tts_tid; /* stored tuple's tid */
130 : : Oid tts_tableOid; /* table oid of tuple */
131 : : } TupleTableSlot;
132 : :
133 : : /* routines for a TupleTableSlot implementation */
134 : : struct TupleTableSlotOps
135 : : {
136 : : /* Minimum size of the slot */
137 : : size_t base_slot_size;
138 : :
139 : : /* Initialization. */
140 : : void (*init) (TupleTableSlot *slot);
141 : :
142 : : /* Destruction. */
143 : : void (*release) (TupleTableSlot *slot);
144 : :
145 : : /*
146 : : * Clear the contents of the slot. Only the contents are expected to be
147 : : * cleared and not the tuple descriptor. Typically an implementation of
148 : : * this callback should free the memory allocated for the tuple contained
149 : : * in the slot.
150 : : */
151 : : void (*clear) (TupleTableSlot *slot);
152 : :
153 : : /*
154 : : * Fill up first natts entries of tts_values and tts_isnull arrays with
155 : : * values from the tuple contained in the slot. The function may be called
156 : : * with natts more than the number of attributes available in the tuple,
157 : : * in which case it should set tts_nvalid to the number of returned
158 : : * columns.
159 : : */
160 : : void (*getsomeattrs) (TupleTableSlot *slot, int natts);
161 : :
162 : : /*
163 : : * Returns value of the given system attribute as a datum and sets isnull
164 : : * to false, if it's not NULL. Throws an error if the slot type does not
165 : : * support system attributes.
166 : : */
167 : : Datum (*getsysattr) (TupleTableSlot *slot, int attnum, bool *isnull);
168 : :
169 : : /*
170 : : * Check if the tuple is created by the current transaction. Throws an
171 : : * error if the slot doesn't contain the storage tuple.
172 : : */
173 : : bool (*is_current_xact_tuple) (TupleTableSlot *slot);
174 : :
175 : : /*
176 : : * Make the contents of the slot solely depend on the slot, and not on
177 : : * underlying resources (like another memory context, buffers, etc).
178 : : */
179 : : void (*materialize) (TupleTableSlot *slot);
180 : :
181 : : /*
182 : : * Copy the contents of the source slot into the destination slot's own
183 : : * context. Invoked using callback of the destination slot. 'dstslot' and
184 : : * 'srcslot' can be assumed to have the same number of attributes.
185 : : */
186 : : void (*copyslot) (TupleTableSlot *dstslot, TupleTableSlot *srcslot);
187 : :
188 : : /*
189 : : * Return a heap tuple "owned" by the slot. It is slot's responsibility to
190 : : * free the memory consumed by the heap tuple. If the slot can not "own" a
191 : : * heap tuple, it should not implement this callback and should set it as
192 : : * NULL.
193 : : */
194 : : HeapTuple (*get_heap_tuple) (TupleTableSlot *slot);
195 : :
196 : : /*
197 : : * Return a minimal tuple "owned" by the slot. It is slot's responsibility
198 : : * to free the memory consumed by the minimal tuple. If the slot can not
199 : : * "own" a minimal tuple, it should not implement this callback and should
200 : : * set it as NULL.
201 : : */
202 : : MinimalTuple (*get_minimal_tuple) (TupleTableSlot *slot);
203 : :
204 : : /*
205 : : * Return a copy of heap tuple representing the contents of the slot. The
206 : : * copy needs to be palloc'd in the current memory context. The slot
207 : : * itself is expected to remain unaffected. It is *not* expected to have
208 : : * meaningful "system columns" in the copy. The copy is not be "owned" by
209 : : * the slot i.e. the caller has to take responsibility to free memory
210 : : * consumed by the slot.
211 : : */
212 : : HeapTuple (*copy_heap_tuple) (TupleTableSlot *slot);
213 : :
214 : : /*
215 : : * Return a copy of minimal tuple representing the contents of the slot.
216 : : * The copy needs to be palloc'd in the current memory context. The slot
217 : : * itself is expected to remain unaffected. It is *not* expected to have
218 : : * meaningful "system columns" in the copy. The copy is not be "owned" by
219 : : * the slot i.e. the caller has to take responsibility to free memory
220 : : * consumed by the slot.
221 : : *
222 : : * The copy has "extra" bytes (maxaligned and zeroed) available before the
223 : : * tuple, which is useful so that some callers may store extra data along
224 : : * with the minimal tuple without the need for an additional allocation.
225 : : */
226 : : MinimalTuple (*copy_minimal_tuple) (TupleTableSlot *slot, Size extra);
227 : : };
228 : :
229 : : /*
230 : : * Predefined TupleTableSlotOps for various types of TupleTableSlotOps. The
231 : : * same are used to identify the type of a given slot.
232 : : */
233 : : extern PGDLLIMPORT const TupleTableSlotOps TTSOpsVirtual;
234 : : extern PGDLLIMPORT const TupleTableSlotOps TTSOpsHeapTuple;
235 : : extern PGDLLIMPORT const TupleTableSlotOps TTSOpsMinimalTuple;
236 : : extern PGDLLIMPORT const TupleTableSlotOps TTSOpsBufferHeapTuple;
237 : :
238 : : #define TTS_IS_VIRTUAL(slot) ((slot)->tts_ops == &TTSOpsVirtual)
239 : : #define TTS_IS_HEAPTUPLE(slot) ((slot)->tts_ops == &TTSOpsHeapTuple)
240 : : #define TTS_IS_MINIMALTUPLE(slot) ((slot)->tts_ops == &TTSOpsMinimalTuple)
241 : : #define TTS_IS_BUFFERTUPLE(slot) ((slot)->tts_ops == &TTSOpsBufferHeapTuple)
242 : :
243 : :
244 : : /*
245 : : * Tuple table slot implementations.
246 : : */
247 : :
248 : : typedef struct VirtualTupleTableSlot
249 : : {
250 : : pg_node_attr(abstract)
251 : :
252 : : TupleTableSlot base;
253 : :
254 : : char *data; /* data for materialized slots */
255 : : } VirtualTupleTableSlot;
256 : :
257 : : typedef struct HeapTupleTableSlot
258 : : {
259 : : pg_node_attr(abstract)
260 : :
261 : : TupleTableSlot base;
262 : :
263 : : #define FIELDNO_HEAPTUPLETABLESLOT_TUPLE 1
264 : : HeapTuple tuple; /* physical tuple */
265 : : #define FIELDNO_HEAPTUPLETABLESLOT_OFF 2
266 : : uint32 off; /* saved state for slot_deform_heap_tuple */
267 : : HeapTupleData tupdata; /* optional workspace for storing tuple */
268 : : } HeapTupleTableSlot;
269 : :
270 : : /* heap tuple residing in a buffer */
271 : : typedef struct BufferHeapTupleTableSlot
272 : : {
273 : : pg_node_attr(abstract)
274 : :
275 : : HeapTupleTableSlot base;
276 : :
277 : : /*
278 : : * If buffer is not InvalidBuffer, then the slot is holding a pin on the
279 : : * indicated buffer page; drop the pin when we release the slot's
280 : : * reference to that buffer. (TTS_FLAG_SHOULDFREE should not be set in
281 : : * such a case, since presumably base.tuple is pointing into the buffer.)
282 : : */
283 : : Buffer buffer; /* tuple's buffer, or InvalidBuffer */
284 : : } BufferHeapTupleTableSlot;
285 : :
286 : : typedef struct MinimalTupleTableSlot
287 : : {
288 : : pg_node_attr(abstract)
289 : :
290 : : TupleTableSlot base;
291 : :
292 : : /*
293 : : * In a minimal slot tuple points at minhdr and the fields of that struct
294 : : * are set correctly for access to the minimal tuple; in particular,
295 : : * minhdr.t_data points MINIMAL_TUPLE_OFFSET bytes before mintuple. This
296 : : * allows column extraction to treat the case identically to regular
297 : : * physical tuples.
298 : : */
299 : : #define FIELDNO_MINIMALTUPLETABLESLOT_TUPLE 1
300 : : HeapTuple tuple; /* tuple wrapper */
301 : : MinimalTuple mintuple; /* minimal tuple, or NULL if none */
302 : : HeapTupleData minhdr; /* workspace for minimal-tuple-only case */
303 : : #define FIELDNO_MINIMALTUPLETABLESLOT_OFF 4
304 : : uint32 off; /* saved state for slot_deform_heap_tuple */
305 : : } MinimalTupleTableSlot;
306 : :
307 : : /*
308 : : * TupIsNull -- is a TupleTableSlot empty?
309 : : */
310 : : #define TupIsNull(slot) \
311 : : ((slot) == NULL || TTS_EMPTY(slot))
312 : :
313 : : /* in executor/execTuples.c */
314 : : extern TupleTableSlot *MakeTupleTableSlot(TupleDesc tupleDesc,
315 : : const TupleTableSlotOps *tts_ops);
316 : : extern TupleTableSlot *ExecAllocTableSlot(List **tupleTable, TupleDesc desc,
317 : : const TupleTableSlotOps *tts_ops);
318 : : extern void ExecResetTupleTable(List *tupleTable, bool shouldFree);
319 : : extern TupleTableSlot *MakeSingleTupleTableSlot(TupleDesc tupdesc,
320 : : const TupleTableSlotOps *tts_ops);
321 : : extern void ExecDropSingleTupleTableSlot(TupleTableSlot *slot);
322 : : extern void ExecSetSlotDescriptor(TupleTableSlot *slot, TupleDesc tupdesc);
323 : : extern TupleTableSlot *ExecStoreHeapTuple(HeapTuple tuple,
324 : : TupleTableSlot *slot,
325 : : bool shouldFree);
326 : : extern void ExecForceStoreHeapTuple(HeapTuple tuple,
327 : : TupleTableSlot *slot,
328 : : bool shouldFree);
329 : : extern TupleTableSlot *ExecStoreBufferHeapTuple(HeapTuple tuple,
330 : : TupleTableSlot *slot,
331 : : Buffer buffer);
332 : : extern TupleTableSlot *ExecStorePinnedBufferHeapTuple(HeapTuple tuple,
333 : : TupleTableSlot *slot,
334 : : Buffer buffer);
335 : : extern TupleTableSlot *ExecStoreMinimalTuple(MinimalTuple mtup,
336 : : TupleTableSlot *slot,
337 : : bool shouldFree);
338 : : extern void ExecForceStoreMinimalTuple(MinimalTuple mtup, TupleTableSlot *slot,
339 : : bool shouldFree);
340 : : extern TupleTableSlot *ExecStoreVirtualTuple(TupleTableSlot *slot);
341 : : extern TupleTableSlot *ExecStoreAllNullTuple(TupleTableSlot *slot);
342 : : extern void ExecStoreHeapTupleDatum(Datum data, TupleTableSlot *slot);
343 : : extern HeapTuple ExecFetchSlotHeapTuple(TupleTableSlot *slot, bool materialize, bool *shouldFree);
344 : : extern MinimalTuple ExecFetchSlotMinimalTuple(TupleTableSlot *slot,
345 : : bool *shouldFree);
346 : : extern Datum ExecFetchSlotHeapTupleDatum(TupleTableSlot *slot);
347 : : extern void slot_getmissingattrs(TupleTableSlot *slot, int startAttNum,
348 : : int lastAttNum);
349 : : extern void slot_getsomeattrs_int(TupleTableSlot *slot, int attnum);
350 : :
351 : :
352 : : #ifndef FRONTEND
353 : :
354 : : /*
355 : : * This function forces the entries of the slot's Datum/isnull arrays to be
356 : : * valid at least up through the attnum'th entry.
357 : : */
358 : : static inline void
2486 andres@anarazel.de 359 :CBC 129265324 : slot_getsomeattrs(TupleTableSlot *slot, int attnum)
360 : : {
361 [ + + ]: 129265324 : if (slot->tts_nvalid < attnum)
362 : 98464626 : slot_getsomeattrs_int(slot, attnum);
363 : 129265324 : }
364 : :
365 : : /*
366 : : * slot_getallattrs
367 : : * This function forces all the entries of the slot's Datum/isnull
368 : : * arrays to be valid. The caller may then extract data directly
369 : : * from those arrays instead of using slot_getattr.
370 : : */
371 : : static inline void
2571 372 : 8905086 : slot_getallattrs(TupleTableSlot *slot)
373 : : {
374 : 8905086 : slot_getsomeattrs(slot, slot->tts_tupleDescriptor->natts);
375 : 8905086 : }
376 : :
377 : :
378 : : /*
379 : : * slot_attisnull
380 : : *
381 : : * Detect whether an attribute of the slot is null, without actually fetching
382 : : * it.
383 : : */
384 : : static inline bool
2486 385 : 5513670 : slot_attisnull(TupleTableSlot *slot, int attnum)
386 : : {
1044 peter@eisentraut.org 387 [ - + ]: 5513670 : Assert(attnum > 0);
388 : :
2486 andres@anarazel.de 389 [ + + ]: 5513670 : if (attnum > slot->tts_nvalid)
390 : 4143478 : slot_getsomeattrs(slot, attnum);
391 : :
392 : 5513670 : return slot->tts_isnull[attnum - 1];
393 : : }
394 : :
395 : : /*
396 : : * slot_getattr - fetch one attribute of the slot's contents.
397 : : */
398 : : static inline Datum
399 : 33926224 : slot_getattr(TupleTableSlot *slot, int attnum,
400 : : bool *isnull)
401 : : {
1044 peter@eisentraut.org 402 [ - + ]: 33926224 : Assert(attnum > 0);
403 : :
2486 andres@anarazel.de 404 [ + + ]: 33926224 : if (attnum > slot->tts_nvalid)
405 : 27070813 : slot_getsomeattrs(slot, attnum);
406 : :
407 : 33926224 : *isnull = slot->tts_isnull[attnum - 1];
408 : :
409 : 33926224 : return slot->tts_values[attnum - 1];
410 : : }
411 : :
412 : : /*
413 : : * slot_getsysattr - fetch a system attribute of the slot's current tuple.
414 : : *
415 : : * If the slot type does not contain system attributes, this will throw an
416 : : * error. Hence before calling this function, callers should make sure that
417 : : * the slot type is the one that supports system attributes.
418 : : */
419 : : static inline Datum
420 : 3822180 : slot_getsysattr(TupleTableSlot *slot, int attnum, bool *isnull)
421 : : {
841 tgl@sss.pgh.pa.us 422 [ - + ]: 3822180 : Assert(attnum < 0); /* caller error */
423 : :
2384 andres@anarazel.de 424 [ + + ]: 3822180 : if (attnum == TableOidAttributeNumber)
425 : : {
426 : 1521226 : *isnull = false;
427 : 1521226 : return ObjectIdGetDatum(slot->tts_tableOid);
428 : : }
429 [ + + ]: 2300954 : else if (attnum == SelfItemPointerAttributeNumber)
430 : : {
431 : 2228468 : *isnull = false;
432 : 2228468 : return PointerGetDatum(&slot->tts_tid);
433 : : }
434 : :
435 : : /* Fetch the system attribute from the underlying tuple. */
2486 436 : 72486 : return slot->tts_ops->getsysattr(slot, attnum, isnull);
437 : : }
438 : :
439 : : /*
440 : : * slot_is_current_xact_tuple - check if the slot's current tuple is created
441 : : * by the current transaction.
442 : : *
443 : : * If the slot does not contain a storage tuple, this will throw an error.
444 : : * Hence before calling this function, callers should make sure that the
445 : : * slot type supports storage tuples and that there is currently one inside
446 : : * the slot.
447 : : */
448 : : static inline bool
534 akorotkov@postgresql 449 : 462 : slot_is_current_xact_tuple(TupleTableSlot *slot)
450 : : {
451 : 462 : return slot->tts_ops->is_current_xact_tuple(slot);
452 : : }
453 : :
454 : : /*
455 : : * ExecClearTuple - clear the slot's contents
456 : : */
457 : : static inline TupleTableSlot *
2486 andres@anarazel.de 458 : 76187791 : ExecClearTuple(TupleTableSlot *slot)
459 : : {
460 : 76187791 : slot->tts_ops->clear(slot);
461 : :
462 : 76187791 : return slot;
463 : : }
464 : :
465 : : /* ExecMaterializeSlot - force a slot into the "materialized" state.
466 : : *
467 : : * This causes the slot's tuple to be a local copy not dependent on any
468 : : * external storage (i.e. pointing into a Buffer, or having allocations in
469 : : * another memory context).
470 : : *
471 : : * A typical use for this operation is to prepare a computed tuple for being
472 : : * stored on disk. The original data may or may not be virtual, but in any
473 : : * case we need a private copy for heap_insert to scribble on.
474 : : */
475 : : static inline void
476 : 8088174 : ExecMaterializeSlot(TupleTableSlot *slot)
477 : : {
478 : 8088174 : slot->tts_ops->materialize(slot);
479 : 8088174 : }
480 : :
481 : : /*
482 : : * ExecCopySlotHeapTuple - return HeapTuple allocated in caller's context
483 : : */
484 : : static inline HeapTuple
485 : 11641625 : ExecCopySlotHeapTuple(TupleTableSlot *slot)
486 : : {
487 [ - + ]: 11641625 : Assert(!TTS_EMPTY(slot));
488 : :
489 : 11641625 : return slot->tts_ops->copy_heap_tuple(slot);
490 : : }
491 : :
492 : : /*
493 : : * ExecCopySlotMinimalTuple - return MinimalTuple allocated in caller's context
494 : : */
495 : : static inline MinimalTuple
496 : 8141360 : ExecCopySlotMinimalTuple(TupleTableSlot *slot)
497 : : {
166 jdavis@postgresql.or 498 : 8141360 : return slot->tts_ops->copy_minimal_tuple(slot, 0);
499 : : }
500 : :
501 : : /*
502 : : * ExecCopySlotMinimalTupleExtra - return MinimalTuple allocated in caller's
503 : : * context, with extra bytes (maxaligned and zeroed) before the tuple for data
504 : : * the caller wishes to store along with the tuple (without requiring the
505 : : * caller to make an additional allocation).
506 : : */
507 : : static inline MinimalTuple
508 : 511067 : ExecCopySlotMinimalTupleExtra(TupleTableSlot *slot, Size extra)
509 : : {
510 : 511067 : return slot->tts_ops->copy_minimal_tuple(slot, extra);
511 : : }
512 : :
513 : : /*
514 : : * ExecCopySlot - copy one slot's contents into another.
515 : : *
516 : : * If a source's system attributes are supposed to be accessed in the target
517 : : * slot, the target slot and source slot types need to match.
518 : : *
519 : : * Currently, 'dstslot' and 'srcslot' must have the same number of attributes.
520 : : * Future work could see this relaxed to allow the source to contain
521 : : * additional attributes and have the code here only copy over the leading
522 : : * attributes.
523 : : */
524 : : static inline TupleTableSlot *
2486 andres@anarazel.de 525 : 6493043 : ExecCopySlot(TupleTableSlot *dstslot, TupleTableSlot *srcslot)
526 : : {
527 [ - + ]: 6493043 : Assert(!TTS_EMPTY(srcslot));
1044 peter@eisentraut.org 528 [ - + ]: 6493043 : Assert(srcslot != dstslot);
639 drowley@postgresql.o 529 [ - + ]: 6493043 : Assert(dstslot->tts_tupleDescriptor->natts ==
530 : : srcslot->tts_tupleDescriptor->natts);
531 : :
2486 andres@anarazel.de 532 : 6493043 : dstslot->tts_ops->copyslot(dstslot, srcslot);
533 : :
534 : 6493043 : return dstslot;
535 : : }
536 : :
537 : : #endif /* FRONTEND */
538 : :
539 : : #endif /* TUPTABLE_H */
|
