Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * tupdesc.c
4 : * POSTGRES tuple descriptor support code
5 : *
6 : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/backend/access/common/tupdesc.c
12 : *
13 : * NOTES
14 : * some of the executor utility code such as "ExecTypeFromTL" should be
15 : * moved here.
16 : *
17 : *-------------------------------------------------------------------------
18 : */
19 :
20 : #include "postgres.h"
21 :
22 : #include "access/htup_details.h"
23 : #include "access/toast_compression.h"
24 : #include "access/tupdesc_details.h"
25 : #include "catalog/catalog.h"
26 : #include "catalog/pg_collation.h"
27 : #include "catalog/pg_type.h"
28 : #include "common/hashfn.h"
29 : #include "utils/builtins.h"
30 : #include "utils/datum.h"
31 : #include "utils/resowner.h"
32 : #include "utils/syscache.h"
33 :
34 : /* ResourceOwner callbacks to hold tupledesc references */
35 : static void ResOwnerReleaseTupleDesc(Datum res);
36 : static char *ResOwnerPrintTupleDesc(Datum res);
37 :
38 : static const ResourceOwnerDesc tupdesc_resowner_desc =
39 : {
40 : .name = "tupdesc reference",
41 : .release_phase = RESOURCE_RELEASE_AFTER_LOCKS,
42 : .release_priority = RELEASE_PRIO_TUPDESC_REFS,
43 : .ReleaseResource = ResOwnerReleaseTupleDesc,
44 : .DebugPrint = ResOwnerPrintTupleDesc
45 : };
46 :
47 : /* Convenience wrappers over ResourceOwnerRemember/Forget */
48 : static inline void
49 21302389 : ResourceOwnerRememberTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
50 : {
51 21302389 : ResourceOwnerRemember(owner, PointerGetDatum(tupdesc), &tupdesc_resowner_desc);
52 21302389 : }
53 :
54 : static inline void
55 21290597 : ResourceOwnerForgetTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
56 : {
57 21290597 : ResourceOwnerForget(owner, PointerGetDatum(tupdesc), &tupdesc_resowner_desc);
58 21290597 : }
59 :
60 : /*
61 : * populate_compact_attribute_internal
62 : * Helper function for populate_compact_attribute()
63 : */
64 : static inline void
65 43234850 : populate_compact_attribute_internal(Form_pg_attribute src,
66 : CompactAttribute *dst)
67 : {
68 43234850 : memset(dst, 0, sizeof(CompactAttribute));
69 :
70 43234850 : dst->attcacheoff = -1;
71 43234850 : dst->attlen = src->attlen;
72 :
73 43234850 : dst->attbyval = src->attbyval;
74 43234850 : dst->attispackable = (src->attstorage != TYPSTORAGE_PLAIN);
75 43234850 : dst->atthasmissing = src->atthasmissing;
76 43234850 : dst->attisdropped = src->attisdropped;
77 43234850 : dst->attgenerated = (src->attgenerated != '\0');
78 :
79 : /*
80 : * Assign nullability status for this column. Assuming that a constraint
81 : * exists, at this point we don't know if a not-null constraint is valid,
82 : * so we assign UNKNOWN unless the table is a catalog, in which case we
83 : * know it's valid.
84 : */
85 67490080 : dst->attnullability = !src->attnotnull ? ATTNULLABLE_UNRESTRICTED :
86 24255230 : IsCatalogRelationOid(src->attrelid) ? ATTNULLABLE_VALID :
87 : ATTNULLABLE_UNKNOWN;
88 :
89 : /* Compute numeric alignment requirement, too */
90 43234850 : dst->attalignby = typalign_to_alignby(src->attalign);
91 43234850 : }
92 :
93 : /*
94 : * populate_compact_attribute
95 : * Fill in the corresponding CompactAttribute element from the
96 : * Form_pg_attribute for the given attribute number. This must be called
97 : * whenever a change is made to a Form_pg_attribute in the TupleDesc.
98 : */
99 : void
100 43234850 : populate_compact_attribute(TupleDesc tupdesc, int attnum)
101 : {
102 43234850 : Form_pg_attribute src = TupleDescAttr(tupdesc, attnum);
103 : CompactAttribute *dst;
104 :
105 : /*
106 : * Don't use TupleDescCompactAttr to prevent infinite recursion in assert
107 : * builds.
108 : */
109 43234850 : dst = &tupdesc->compact_attrs[attnum];
110 :
111 43234850 : populate_compact_attribute_internal(src, dst);
112 43234850 : }
113 :
114 : /*
115 : * verify_compact_attribute
116 : * In Assert enabled builds, we verify that the CompactAttribute is
117 : * populated correctly. This helps find bugs in places such as ALTER
118 : * TABLE where code makes changes to the FormData_pg_attribute but
119 : * forgets to call populate_compact_attribute().
120 : *
121 : * This is used in TupleDescCompactAttr(), but declared here to allow access
122 : * to populate_compact_attribute_internal().
123 : */
124 : void
125 0 : verify_compact_attribute(TupleDesc tupdesc, int attnum)
126 : {
127 : #ifdef USE_ASSERT_CHECKING
128 : CompactAttribute cattr;
129 : Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum);
130 : CompactAttribute tmp;
131 :
132 : /*
133 : * Make a temp copy of the TupleDesc's CompactAttribute. This may be a
134 : * shared TupleDesc and the attcacheoff might get changed by another
135 : * backend.
136 : */
137 : memcpy(&cattr, &tupdesc->compact_attrs[attnum], sizeof(CompactAttribute));
138 :
139 : /*
140 : * Populate the temporary CompactAttribute from the corresponding
141 : * Form_pg_attribute
142 : */
143 : populate_compact_attribute_internal(attr, &tmp);
144 :
145 : /*
146 : * Make the attcacheoff match since it's been reset to -1 by
147 : * populate_compact_attribute_internal. Same with attnullability.
148 : */
149 : tmp.attcacheoff = cattr.attcacheoff;
150 : tmp.attnullability = cattr.attnullability;
151 :
152 : /* Check the freshly populated CompactAttribute matches the TupleDesc's */
153 : Assert(memcmp(&tmp, &cattr, sizeof(CompactAttribute)) == 0);
154 : #endif
155 0 : }
156 :
157 : /*
158 : * CreateTemplateTupleDesc
159 : * This function allocates an empty tuple descriptor structure.
160 : *
161 : * Tuple type ID information is initially set for an anonymous record type;
162 : * caller can overwrite this if needed.
163 : */
164 : TupleDesc
165 6566838 : CreateTemplateTupleDesc(int natts)
166 : {
167 : TupleDesc desc;
168 :
169 : /*
170 : * sanity checks
171 : */
172 : Assert(natts >= 0);
173 :
174 : /*
175 : * Allocate enough memory for the tuple descriptor, the CompactAttribute
176 : * array and also an array of FormData_pg_attribute.
177 : *
178 : * Note: the FormData_pg_attribute array stride is
179 : * sizeof(FormData_pg_attribute), since we declare the array elements as
180 : * FormData_pg_attribute for notational convenience. However, we only
181 : * guarantee that the first ATTRIBUTE_FIXED_PART_SIZE bytes of each entry
182 : * are valid; most code that copies tupdesc entries around copies just
183 : * that much. In principle that could be less due to trailing padding,
184 : * although with the current definition of pg_attribute there probably
185 : * isn't any padding.
186 : */
187 6566838 : desc = (TupleDesc) palloc(offsetof(struct TupleDescData, compact_attrs) +
188 : natts * sizeof(CompactAttribute) +
189 6566838 : natts * sizeof(FormData_pg_attribute));
190 :
191 : /*
192 : * Initialize other fields of the tupdesc.
193 : */
194 6566838 : desc->natts = natts;
195 6566838 : desc->constr = NULL;
196 6566838 : desc->tdtypeid = RECORDOID;
197 6566838 : desc->tdtypmod = -1;
198 6566838 : desc->tdrefcount = -1; /* assume not reference-counted */
199 :
200 : /* This will be set to the correct value by TupleDescFinalize() */
201 6566838 : desc->firstNonCachedOffsetAttr = -1;
202 6566838 : desc->firstNonGuaranteedAttr = -1;
203 :
204 6566838 : return desc;
205 : }
206 :
207 : /*
208 : * CreateTupleDesc
209 : * This function allocates a new TupleDesc by copying a given
210 : * Form_pg_attribute array.
211 : *
212 : * Tuple type ID information is initially set for an anonymous record type;
213 : * caller can overwrite this if needed.
214 : */
215 : TupleDesc
216 666672 : CreateTupleDesc(int natts, Form_pg_attribute *attrs)
217 : {
218 : TupleDesc desc;
219 : int i;
220 :
221 666672 : desc = CreateTemplateTupleDesc(natts);
222 :
223 10162074 : for (i = 0; i < natts; ++i)
224 : {
225 9495402 : memcpy(TupleDescAttr(desc, i), attrs[i], ATTRIBUTE_FIXED_PART_SIZE);
226 9495402 : populate_compact_attribute(desc, i);
227 : }
228 :
229 666672 : TupleDescFinalize(desc);
230 :
231 666672 : return desc;
232 : }
233 :
234 : /*
235 : * CreateTupleDescCopy
236 : * This function creates a new TupleDesc by copying from an existing
237 : * TupleDesc.
238 : *
239 : * !!! Constraints and defaults are not copied !!!
240 : */
241 : TupleDesc
242 259571 : CreateTupleDescCopy(TupleDesc tupdesc)
243 : {
244 : TupleDesc desc;
245 : int i;
246 :
247 259571 : desc = CreateTemplateTupleDesc(tupdesc->natts);
248 :
249 : /* Flat-copy the attribute array (unless there are no attributes) */
250 259571 : if (desc->natts > 0)
251 257187 : memcpy(TupleDescAttr(desc, 0),
252 257187 : TupleDescAttr(tupdesc, 0),
253 257187 : desc->natts * sizeof(FormData_pg_attribute));
254 :
255 : /*
256 : * Since we're not copying constraints and defaults, clear fields
257 : * associated with them.
258 : */
259 1299146 : for (i = 0; i < desc->natts; i++)
260 : {
261 1039575 : Form_pg_attribute att = TupleDescAttr(desc, i);
262 :
263 1039575 : att->attnotnull = false;
264 1039575 : att->atthasdef = false;
265 1039575 : att->atthasmissing = false;
266 1039575 : att->attidentity = '\0';
267 1039575 : att->attgenerated = '\0';
268 :
269 1039575 : populate_compact_attribute(desc, i);
270 : }
271 :
272 : /* We can copy the tuple type identification, too */
273 259571 : desc->tdtypeid = tupdesc->tdtypeid;
274 259571 : desc->tdtypmod = tupdesc->tdtypmod;
275 :
276 259571 : TupleDescFinalize(desc);
277 :
278 259571 : return desc;
279 : }
280 :
281 : /*
282 : * CreateTupleDescTruncatedCopy
283 : * This function creates a new TupleDesc with only the first 'natts'
284 : * attributes from an existing TupleDesc
285 : *
286 : * !!! Constraints and defaults are not copied !!!
287 : */
288 : TupleDesc
289 25595 : CreateTupleDescTruncatedCopy(TupleDesc tupdesc, int natts)
290 : {
291 : TupleDesc desc;
292 : int i;
293 :
294 : Assert(natts <= tupdesc->natts);
295 :
296 25595 : desc = CreateTemplateTupleDesc(natts);
297 :
298 : /* Flat-copy the attribute array (unless there are no attributes) */
299 25595 : if (desc->natts > 0)
300 25595 : memcpy(TupleDescAttr(desc, 0),
301 25595 : TupleDescAttr(tupdesc, 0),
302 25595 : desc->natts * sizeof(FormData_pg_attribute));
303 :
304 : /*
305 : * Since we're not copying constraints and defaults, clear fields
306 : * associated with them.
307 : */
308 62372 : for (i = 0; i < desc->natts; i++)
309 : {
310 36777 : Form_pg_attribute att = TupleDescAttr(desc, i);
311 :
312 36777 : att->attnotnull = false;
313 36777 : att->atthasdef = false;
314 36777 : att->atthasmissing = false;
315 36777 : att->attidentity = '\0';
316 36777 : att->attgenerated = '\0';
317 :
318 36777 : populate_compact_attribute(desc, i);
319 : }
320 :
321 : /* We can copy the tuple type identification, too */
322 25595 : desc->tdtypeid = tupdesc->tdtypeid;
323 25595 : desc->tdtypmod = tupdesc->tdtypmod;
324 :
325 25595 : TupleDescFinalize(desc);
326 :
327 25595 : return desc;
328 : }
329 :
330 : /*
331 : * CreateTupleDescCopyConstr
332 : * This function creates a new TupleDesc by copying from an existing
333 : * TupleDesc (including its constraints and defaults).
334 : */
335 : TupleDesc
336 528769 : CreateTupleDescCopyConstr(TupleDesc tupdesc)
337 : {
338 : TupleDesc desc;
339 528769 : TupleConstr *constr = tupdesc->constr;
340 : int i;
341 :
342 528769 : desc = CreateTemplateTupleDesc(tupdesc->natts);
343 :
344 : /* Flat-copy the attribute array (unless there are no attributes) */
345 528769 : if (desc->natts > 0)
346 528707 : memcpy(TupleDescAttr(desc, 0),
347 528707 : TupleDescAttr(tupdesc, 0),
348 528707 : desc->natts * sizeof(FormData_pg_attribute));
349 :
350 7631792 : for (i = 0; i < desc->natts; i++)
351 : {
352 7103023 : populate_compact_attribute(desc, i);
353 :
354 7103023 : TupleDescCompactAttr(desc, i)->attnullability =
355 14206046 : TupleDescCompactAttr(tupdesc, i)->attnullability;
356 : }
357 :
358 : /* Copy the TupleConstr data structure, if any */
359 528769 : if (constr)
360 : {
361 483549 : TupleConstr *cpy = palloc0_object(TupleConstr);
362 :
363 483549 : cpy->has_not_null = constr->has_not_null;
364 483549 : cpy->has_generated_stored = constr->has_generated_stored;
365 483549 : cpy->has_generated_virtual = constr->has_generated_virtual;
366 :
367 483549 : if ((cpy->num_defval = constr->num_defval) > 0)
368 : {
369 2949 : cpy->defval = (AttrDefault *) palloc(cpy->num_defval * sizeof(AttrDefault));
370 2949 : memcpy(cpy->defval, constr->defval, cpy->num_defval * sizeof(AttrDefault));
371 7161 : for (i = cpy->num_defval - 1; i >= 0; i--)
372 4212 : cpy->defval[i].adbin = pstrdup(constr->defval[i].adbin);
373 : }
374 :
375 483549 : if (constr->missing)
376 : {
377 426 : cpy->missing = (AttrMissing *) palloc(tupdesc->natts * sizeof(AttrMissing));
378 426 : memcpy(cpy->missing, constr->missing, tupdesc->natts * sizeof(AttrMissing));
379 3278 : for (i = tupdesc->natts - 1; i >= 0; i--)
380 : {
381 2852 : if (constr->missing[i].am_present)
382 : {
383 762 : CompactAttribute *attr = TupleDescCompactAttr(tupdesc, i);
384 :
385 762 : cpy->missing[i].am_value = datumCopy(constr->missing[i].am_value,
386 762 : attr->attbyval,
387 762 : attr->attlen);
388 : }
389 : }
390 : }
391 :
392 483549 : if ((cpy->num_check = constr->num_check) > 0)
393 : {
394 1787 : cpy->check = (ConstrCheck *) palloc(cpy->num_check * sizeof(ConstrCheck));
395 1787 : memcpy(cpy->check, constr->check, cpy->num_check * sizeof(ConstrCheck));
396 5319 : for (i = cpy->num_check - 1; i >= 0; i--)
397 : {
398 3532 : cpy->check[i].ccname = pstrdup(constr->check[i].ccname);
399 3532 : cpy->check[i].ccbin = pstrdup(constr->check[i].ccbin);
400 3532 : cpy->check[i].ccenforced = constr->check[i].ccenforced;
401 3532 : cpy->check[i].ccvalid = constr->check[i].ccvalid;
402 3532 : cpy->check[i].ccnoinherit = constr->check[i].ccnoinherit;
403 : }
404 : }
405 :
406 483549 : desc->constr = cpy;
407 : }
408 :
409 : /* We can copy the tuple type identification, too */
410 528769 : desc->tdtypeid = tupdesc->tdtypeid;
411 528769 : desc->tdtypmod = tupdesc->tdtypmod;
412 :
413 528769 : TupleDescFinalize(desc);
414 :
415 528769 : return desc;
416 : }
417 :
418 : /*
419 : * TupleDescCopy
420 : * Copy a tuple descriptor into caller-supplied memory.
421 : * The memory may be shared memory mapped at any address, and must
422 : * be sufficient to hold TupleDescSize(src) bytes.
423 : *
424 : * !!! Constraints and defaults are not copied !!!
425 : */
426 : void
427 236 : TupleDescCopy(TupleDesc dst, TupleDesc src)
428 : {
429 : int i;
430 :
431 : /* Flat-copy the header and attribute arrays */
432 236 : memcpy(dst, src, TupleDescSize(src));
433 :
434 : /*
435 : * Since we're not copying constraints and defaults, clear fields
436 : * associated with them.
437 : */
438 933 : for (i = 0; i < dst->natts; i++)
439 : {
440 697 : Form_pg_attribute att = TupleDescAttr(dst, i);
441 :
442 697 : att->attnotnull = false;
443 697 : att->atthasdef = false;
444 697 : att->atthasmissing = false;
445 697 : att->attidentity = '\0';
446 697 : att->attgenerated = '\0';
447 :
448 697 : populate_compact_attribute(dst, i);
449 : }
450 236 : dst->constr = NULL;
451 :
452 : /*
453 : * Also, assume the destination is not to be ref-counted. (Copying the
454 : * source's refcount would be wrong in any case.)
455 : */
456 236 : dst->tdrefcount = -1;
457 :
458 236 : TupleDescFinalize(dst);
459 236 : }
460 :
461 : /*
462 : * TupleDescCopyEntry
463 : * This function copies a single attribute structure from one tuple
464 : * descriptor to another.
465 : *
466 : * !!! Constraints and defaults are not copied !!!
467 : *
468 : * The caller must take care of calling TupleDescFinalize() on 'dst' once all
469 : * TupleDesc changes have been made.
470 : */
471 : void
472 2864 : TupleDescCopyEntry(TupleDesc dst, AttrNumber dstAttno,
473 : TupleDesc src, AttrNumber srcAttno)
474 : {
475 2864 : Form_pg_attribute dstAtt = TupleDescAttr(dst, dstAttno - 1);
476 2864 : Form_pg_attribute srcAtt = TupleDescAttr(src, srcAttno - 1);
477 :
478 : /*
479 : * sanity checks
480 : */
481 : Assert(src);
482 : Assert(dst);
483 : Assert(srcAttno >= 1);
484 : Assert(srcAttno <= src->natts);
485 : Assert(dstAttno >= 1);
486 : Assert(dstAttno <= dst->natts);
487 :
488 2864 : memcpy(dstAtt, srcAtt, ATTRIBUTE_FIXED_PART_SIZE);
489 :
490 2864 : dstAtt->attnum = dstAttno;
491 :
492 : /* since we're not copying constraints or defaults, clear these */
493 2864 : dstAtt->attnotnull = false;
494 2864 : dstAtt->atthasdef = false;
495 2864 : dstAtt->atthasmissing = false;
496 2864 : dstAtt->attidentity = '\0';
497 2864 : dstAtt->attgenerated = '\0';
498 :
499 2864 : populate_compact_attribute(dst, dstAttno - 1);
500 2864 : }
501 :
502 : /*
503 : * TupleDescFinalize
504 : * Finalize the given TupleDesc. This must be called after the
505 : * attributes arrays have been populated or adjusted by any code.
506 : *
507 : * Must be called after populate_compact_attribute() and before
508 : * BlessTupleDesc().
509 : */
510 : void
511 6701042 : TupleDescFinalize(TupleDesc tupdesc)
512 : {
513 6701042 : int firstNonCachedOffsetAttr = 0;
514 6701042 : int firstNonGuaranteedAttr = tupdesc->natts;
515 6701042 : int off = 0;
516 :
517 37237353 : for (int i = 0; i < tupdesc->natts; i++)
518 : {
519 33926564 : CompactAttribute *cattr = TupleDescCompactAttr(tupdesc, i);
520 33926564 : Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
521 :
522 : /*
523 : * Find the highest attnum which is guaranteed to exist in all tuples
524 : * in the table. We currently only pay attention to byval attributes
525 : * to allow additional optimizations during tuple deformation.
526 : */
527 33926564 : if (firstNonGuaranteedAttr == tupdesc->natts &&
528 14146559 : (cattr->attnullability != ATTNULLABLE_VALID || !cattr->attbyval ||
529 7988403 : cattr->atthasmissing || cattr->attisdropped ||
530 7988403 : cattr->attlen <= 0 ||
531 7988403 : attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL))
532 6158362 : firstNonGuaranteedAttr = i;
533 :
534 : /*
535 : * Don't cache offsets beyond fixed-width attributes. Virtual
536 : * generated attributes are stored as NULLs in the tuple, so we don't
537 : * cache offsets beyond these.
538 : */
539 33926564 : if (cattr->attlen <= 0 ||
540 30541758 : attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
541 : break;
542 :
543 30536311 : off = att_nominal_alignby(off, cattr->attalignby);
544 :
545 : /*
546 : * attcacheoff is an int16, so don't try to cache any offsets larger
547 : * than will fit in that type. Any attributes which are offset more
548 : * than 2^15 are likely due to variable-length attributes. Since we
549 : * don't cache offsets for or beyond variable-length attributes, using
550 : * an int16 rather than an int32 here is unlikely to cost us anything.
551 : */
552 30536311 : if (off > PG_INT16_MAX)
553 0 : break;
554 :
555 30536311 : cattr->attcacheoff = (int16) off;
556 :
557 30536311 : off += cattr->attlen;
558 30536311 : firstNonCachedOffsetAttr = i + 1;
559 : }
560 :
561 6701042 : tupdesc->firstNonCachedOffsetAttr = firstNonCachedOffsetAttr;
562 6701042 : tupdesc->firstNonGuaranteedAttr = firstNonGuaranteedAttr;
563 6701042 : }
564 :
565 : /*
566 : * Free a TupleDesc including all substructure
567 : */
568 : void
569 988531 : FreeTupleDesc(TupleDesc tupdesc)
570 : {
571 : int i;
572 :
573 : /*
574 : * Possibly this should assert tdrefcount == 0, to disallow explicit
575 : * freeing of un-refcounted tupdescs?
576 : */
577 : Assert(tupdesc->tdrefcount <= 0);
578 :
579 988531 : if (tupdesc->constr)
580 : {
581 305747 : if (tupdesc->constr->num_defval > 0)
582 : {
583 23477 : AttrDefault *attrdef = tupdesc->constr->defval;
584 :
585 57295 : for (i = tupdesc->constr->num_defval - 1; i >= 0; i--)
586 33818 : pfree(attrdef[i].adbin);
587 23477 : pfree(attrdef);
588 : }
589 305747 : if (tupdesc->constr->missing)
590 : {
591 2534 : AttrMissing *attrmiss = tupdesc->constr->missing;
592 :
593 17946 : for (i = tupdesc->natts - 1; i >= 0; i--)
594 : {
595 15412 : if (attrmiss[i].am_present
596 5315 : && !TupleDescAttr(tupdesc, i)->attbyval)
597 2021 : pfree(DatumGetPointer(attrmiss[i].am_value));
598 : }
599 2534 : pfree(attrmiss);
600 : }
601 305747 : if (tupdesc->constr->num_check > 0)
602 : {
603 8440 : ConstrCheck *check = tupdesc->constr->check;
604 :
605 23500 : for (i = tupdesc->constr->num_check - 1; i >= 0; i--)
606 : {
607 15060 : pfree(check[i].ccname);
608 15060 : pfree(check[i].ccbin);
609 : }
610 8440 : pfree(check);
611 : }
612 305747 : pfree(tupdesc->constr);
613 : }
614 :
615 988531 : pfree(tupdesc);
616 988531 : }
617 :
618 : /*
619 : * Increment the reference count of a tupdesc, and log the reference in
620 : * CurrentResourceOwner.
621 : *
622 : * Do not apply this to tupdescs that are not being refcounted. (Use the
623 : * macro PinTupleDesc for tupdescs of uncertain status.)
624 : */
625 : void
626 21302389 : IncrTupleDescRefCount(TupleDesc tupdesc)
627 : {
628 : Assert(tupdesc->tdrefcount >= 0);
629 :
630 21302389 : ResourceOwnerEnlarge(CurrentResourceOwner);
631 21302389 : tupdesc->tdrefcount++;
632 21302389 : ResourceOwnerRememberTupleDesc(CurrentResourceOwner, tupdesc);
633 21302389 : }
634 :
635 : /*
636 : * Decrement the reference count of a tupdesc, remove the corresponding
637 : * reference from CurrentResourceOwner, and free the tupdesc if no more
638 : * references remain.
639 : *
640 : * Do not apply this to tupdescs that are not being refcounted. (Use the
641 : * macro ReleaseTupleDesc for tupdescs of uncertain status.)
642 : */
643 : void
644 21290597 : DecrTupleDescRefCount(TupleDesc tupdesc)
645 : {
646 : Assert(tupdesc->tdrefcount > 0);
647 :
648 21290597 : ResourceOwnerForgetTupleDesc(CurrentResourceOwner, tupdesc);
649 21290597 : if (--tupdesc->tdrefcount == 0)
650 0 : FreeTupleDesc(tupdesc);
651 21290597 : }
652 :
653 : /*
654 : * Compare two TupleDesc structures for logical equality
655 : */
656 : bool
657 282488 : equalTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2)
658 : {
659 : int i,
660 : n;
661 :
662 282488 : if (tupdesc1->natts != tupdesc2->natts)
663 1946 : return false;
664 280542 : if (tupdesc1->tdtypeid != tupdesc2->tdtypeid)
665 0 : return false;
666 :
667 : /* tdtypmod and tdrefcount are not checked */
668 :
669 1318079 : for (i = 0; i < tupdesc1->natts; i++)
670 : {
671 1047684 : Form_pg_attribute attr1 = TupleDescAttr(tupdesc1, i);
672 1047684 : Form_pg_attribute attr2 = TupleDescAttr(tupdesc2, i);
673 :
674 : /*
675 : * We do not need to check every single field here: we can disregard
676 : * attrelid and attnum (which were used to place the row in the attrs
677 : * array in the first place). It might look like we could dispense
678 : * with checking attlen/attbyval/attalign, since these are derived
679 : * from atttypid; but in the case of dropped columns we must check
680 : * them (since atttypid will be zero for all dropped columns) and in
681 : * general it seems safer to check them always.
682 : *
683 : * We intentionally ignore atthasmissing, since that's not very
684 : * relevant in tupdescs, which lack the attmissingval field.
685 : */
686 1047684 : if (strcmp(NameStr(attr1->attname), NameStr(attr2->attname)) != 0)
687 926 : return false;
688 1046758 : if (attr1->atttypid != attr2->atttypid)
689 758 : return false;
690 1046000 : if (attr1->attlen != attr2->attlen)
691 6 : return false;
692 1045994 : if (attr1->attndims != attr2->attndims)
693 0 : return false;
694 1045994 : if (attr1->atttypmod != attr2->atttypmod)
695 28 : return false;
696 1045966 : if (attr1->attbyval != attr2->attbyval)
697 34 : return false;
698 1045932 : if (attr1->attalign != attr2->attalign)
699 0 : return false;
700 1045932 : if (attr1->attstorage != attr2->attstorage)
701 157 : return false;
702 1045775 : if (attr1->attcompression != attr2->attcompression)
703 44 : return false;
704 1045731 : if (attr1->attnotnull != attr2->attnotnull)
705 1166 : return false;
706 :
707 : /*
708 : * When the column has a not-null constraint, we also need to consider
709 : * its validity aspect, which only manifests in CompactAttribute->
710 : * attnullability, so verify that.
711 : */
712 1044565 : if (attr1->attnotnull)
713 : {
714 343083 : CompactAttribute *cattr1 = TupleDescCompactAttr(tupdesc1, i);
715 343083 : CompactAttribute *cattr2 = TupleDescCompactAttr(tupdesc2, i);
716 :
717 : Assert(cattr1->attnullability != ATTNULLABLE_UNKNOWN);
718 : Assert((cattr1->attnullability == ATTNULLABLE_UNKNOWN) ==
719 : (cattr2->attnullability == ATTNULLABLE_UNKNOWN));
720 :
721 343083 : if (cattr1->attnullability != cattr2->attnullability)
722 70 : return false;
723 : }
724 1044495 : if (attr1->atthasdef != attr2->atthasdef)
725 3682 : return false;
726 1040813 : if (attr1->attidentity != attr2->attidentity)
727 118 : return false;
728 1040695 : if (attr1->attgenerated != attr2->attgenerated)
729 13 : return false;
730 1040682 : if (attr1->attisdropped != attr2->attisdropped)
731 0 : return false;
732 1040682 : if (attr1->attislocal != attr2->attislocal)
733 2640 : return false;
734 1038042 : if (attr1->attinhcount != attr2->attinhcount)
735 505 : return false;
736 1037537 : if (attr1->attcollation != attr2->attcollation)
737 0 : return false;
738 : /* variable-length fields are not even present... */
739 : }
740 :
741 270395 : if (tupdesc1->constr != NULL)
742 : {
743 99695 : TupleConstr *constr1 = tupdesc1->constr;
744 99695 : TupleConstr *constr2 = tupdesc2->constr;
745 :
746 99695 : if (constr2 == NULL)
747 175 : return false;
748 99520 : if (constr1->has_not_null != constr2->has_not_null)
749 0 : return false;
750 99520 : if (constr1->has_generated_stored != constr2->has_generated_stored)
751 468 : return false;
752 99052 : if (constr1->has_generated_virtual != constr2->has_generated_virtual)
753 290 : return false;
754 98762 : n = constr1->num_defval;
755 98762 : if (n != (int) constr2->num_defval)
756 0 : return false;
757 : /* We assume here that both AttrDefault arrays are in adnum order */
758 112192 : for (i = 0; i < n; i++)
759 : {
760 13430 : AttrDefault *defval1 = constr1->defval + i;
761 13430 : AttrDefault *defval2 = constr2->defval + i;
762 :
763 13430 : if (defval1->adnum != defval2->adnum)
764 0 : return false;
765 13430 : if (strcmp(defval1->adbin, defval2->adbin) != 0)
766 0 : return false;
767 : }
768 98762 : if (constr1->missing)
769 : {
770 520 : if (!constr2->missing)
771 65 : return false;
772 2670 : for (i = 0; i < tupdesc1->natts; i++)
773 : {
774 2316 : AttrMissing *missval1 = constr1->missing + i;
775 2316 : AttrMissing *missval2 = constr2->missing + i;
776 :
777 2316 : if (missval1->am_present != missval2->am_present)
778 101 : return false;
779 2215 : if (missval1->am_present)
780 : {
781 757 : CompactAttribute *missatt1 = TupleDescCompactAttr(tupdesc1, i);
782 :
783 757 : if (!datumIsEqual(missval1->am_value, missval2->am_value,
784 757 : missatt1->attbyval, missatt1->attlen))
785 0 : return false;
786 : }
787 : }
788 : }
789 98242 : else if (constr2->missing)
790 251 : return false;
791 98345 : n = constr1->num_check;
792 98345 : if (n != (int) constr2->num_check)
793 1179 : return false;
794 :
795 : /*
796 : * Similarly, we rely here on the ConstrCheck entries being sorted by
797 : * name. If there are duplicate names, the outcome of the comparison
798 : * is uncertain, but that should not happen.
799 : */
800 100000 : for (i = 0; i < n; i++)
801 : {
802 2978 : ConstrCheck *check1 = constr1->check + i;
803 2978 : ConstrCheck *check2 = constr2->check + i;
804 :
805 2978 : if (!(strcmp(check1->ccname, check2->ccname) == 0 &&
806 2978 : strcmp(check1->ccbin, check2->ccbin) == 0 &&
807 2978 : check1->ccenforced == check2->ccenforced &&
808 2890 : check1->ccvalid == check2->ccvalid &&
809 2834 : check1->ccnoinherit == check2->ccnoinherit))
810 144 : return false;
811 : }
812 : }
813 170700 : else if (tupdesc2->constr != NULL)
814 1321 : return false;
815 266401 : return true;
816 : }
817 :
818 : /*
819 : * equalRowTypes
820 : *
821 : * This determines whether two tuple descriptors have equal row types. This
822 : * only checks those fields in pg_attribute that are applicable for row types,
823 : * while ignoring those fields that define the physical row storage or those
824 : * that define table column metadata.
825 : *
826 : * Specifically, this checks:
827 : *
828 : * - same number of attributes
829 : * - same composite type ID (but could both be zero)
830 : * - corresponding attributes (in order) have same the name, type, typmod,
831 : * collation
832 : *
833 : * This is used to check whether two record types are compatible, whether
834 : * function return row types are the same, and other similar situations.
835 : *
836 : * (XXX There was some discussion whether attndims should be checked here, but
837 : * for now it has been decided not to.)
838 : *
839 : * Note: We deliberately do not check the tdtypmod field. This allows
840 : * typcache.c to use this routine to see if a cached record type matches a
841 : * requested type.
842 : */
843 : bool
844 270181 : equalRowTypes(TupleDesc tupdesc1, TupleDesc tupdesc2)
845 : {
846 270181 : if (tupdesc1->natts != tupdesc2->natts)
847 110 : return false;
848 270071 : if (tupdesc1->tdtypeid != tupdesc2->tdtypeid)
849 1283 : return false;
850 :
851 3626187 : for (int i = 0; i < tupdesc1->natts; i++)
852 : {
853 3363176 : Form_pg_attribute attr1 = TupleDescAttr(tupdesc1, i);
854 3363176 : Form_pg_attribute attr2 = TupleDescAttr(tupdesc2, i);
855 :
856 3363176 : if (strcmp(NameStr(attr1->attname), NameStr(attr2->attname)) != 0)
857 5761 : return false;
858 3357415 : if (attr1->atttypid != attr2->atttypid)
859 14 : return false;
860 3357401 : if (attr1->atttypmod != attr2->atttypmod)
861 2 : return false;
862 3357399 : if (attr1->attcollation != attr2->attcollation)
863 0 : return false;
864 :
865 : /* Record types derived from tables could have dropped fields. */
866 3357399 : if (attr1->attisdropped != attr2->attisdropped)
867 0 : return false;
868 : }
869 :
870 263011 : return true;
871 : }
872 :
873 : /*
874 : * hashRowType
875 : *
876 : * If two tuple descriptors would be considered equal by equalRowTypes()
877 : * then their hash value will be equal according to this function.
878 : */
879 : uint32
880 278606 : hashRowType(TupleDesc desc)
881 : {
882 : uint32 s;
883 : int i;
884 :
885 278606 : s = hash_combine(0, hash_bytes_uint32(desc->natts));
886 278606 : s = hash_combine(s, hash_bytes_uint32(desc->tdtypeid));
887 3803816 : for (i = 0; i < desc->natts; ++i)
888 3525210 : s = hash_combine(s, hash_bytes_uint32(TupleDescAttr(desc, i)->atttypid));
889 :
890 278606 : return s;
891 : }
892 :
893 : /*
894 : * TupleDescInitEntry
895 : * This function initializes a single attribute structure in
896 : * a previously allocated tuple descriptor.
897 : *
898 : * If attributeName is NULL, the attname field is set to an empty string
899 : * (this is for cases where we don't know or need a name for the field).
900 : * Also, some callers use this function to change the datatype-related fields
901 : * in an existing tupdesc; they pass attributeName = NameStr(att->attname)
902 : * to indicate that the attname field shouldn't be modified.
903 : *
904 : * Note that attcollation is set to the default for the specified datatype.
905 : * If a nondefault collation is needed, insert it afterwards using
906 : * TupleDescInitEntryCollation.
907 : */
908 : void
909 7873144 : TupleDescInitEntry(TupleDesc desc,
910 : AttrNumber attributeNumber,
911 : const char *attributeName,
912 : Oid oidtypeid,
913 : int32 typmod,
914 : int attdim)
915 : {
916 : HeapTuple tuple;
917 : Form_pg_type typeForm;
918 : Form_pg_attribute att;
919 :
920 : /*
921 : * sanity checks
922 : */
923 : Assert(desc);
924 : Assert(attributeNumber >= 1);
925 : Assert(attributeNumber <= desc->natts);
926 : Assert(attdim >= 0);
927 : Assert(attdim <= PG_INT16_MAX);
928 :
929 : /*
930 : * initialize the attribute fields
931 : */
932 7873144 : att = TupleDescAttr(desc, attributeNumber - 1);
933 :
934 7873144 : att->attrelid = 0; /* dummy value */
935 :
936 : /*
937 : * Note: attributeName can be NULL, because the planner doesn't always
938 : * fill in valid resname values in targetlists, particularly for resjunk
939 : * attributes. Also, do nothing if caller wants to re-use the old attname.
940 : */
941 7873144 : if (attributeName == NULL)
942 12822353 : MemSet(NameStr(att->attname), 0, NAMEDATALEN);
943 5134511 : else if (attributeName != NameStr(att->attname))
944 5132086 : namestrcpy(&(att->attname), attributeName);
945 :
946 7873144 : att->atttypmod = typmod;
947 :
948 7873144 : att->attnum = attributeNumber;
949 7873144 : att->attndims = attdim;
950 :
951 7873144 : att->attnotnull = false;
952 7873144 : att->atthasdef = false;
953 7873144 : att->atthasmissing = false;
954 7873144 : att->attidentity = '\0';
955 7873144 : att->attgenerated = '\0';
956 7873144 : att->attisdropped = false;
957 7873144 : att->attislocal = true;
958 7873144 : att->attinhcount = 0;
959 : /* variable-length fields are not present in tupledescs */
960 :
961 7873144 : tuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(oidtypeid));
962 7873144 : if (!HeapTupleIsValid(tuple))
963 0 : elog(ERROR, "cache lookup failed for type %u", oidtypeid);
964 7873144 : typeForm = (Form_pg_type) GETSTRUCT(tuple);
965 :
966 7873144 : att->atttypid = oidtypeid;
967 7873144 : att->attlen = typeForm->typlen;
968 7873144 : att->attbyval = typeForm->typbyval;
969 7873144 : att->attalign = typeForm->typalign;
970 7873144 : att->attstorage = typeForm->typstorage;
971 7873144 : att->attcompression = InvalidCompressionMethod;
972 7873144 : att->attcollation = typeForm->typcollation;
973 :
974 7873144 : populate_compact_attribute(desc, attributeNumber - 1);
975 :
976 7873144 : ReleaseSysCache(tuple);
977 7873144 : }
978 :
979 : /*
980 : * TupleDescInitBuiltinEntry
981 : * Initialize a tuple descriptor without catalog access. Only
982 : * a limited range of builtin types are supported.
983 : */
984 : void
985 8339 : TupleDescInitBuiltinEntry(TupleDesc desc,
986 : AttrNumber attributeNumber,
987 : const char *attributeName,
988 : Oid oidtypeid,
989 : int32 typmod,
990 : int attdim)
991 : {
992 : Form_pg_attribute att;
993 :
994 : /* sanity checks */
995 : Assert(desc);
996 : Assert(attributeNumber >= 1);
997 : Assert(attributeNumber <= desc->natts);
998 : Assert(attdim >= 0);
999 : Assert(attdim <= PG_INT16_MAX);
1000 :
1001 : /* initialize the attribute fields */
1002 8339 : att = TupleDescAttr(desc, attributeNumber - 1);
1003 8339 : att->attrelid = 0; /* dummy value */
1004 :
1005 : /* unlike TupleDescInitEntry, we require an attribute name */
1006 : Assert(attributeName != NULL);
1007 8339 : namestrcpy(&(att->attname), attributeName);
1008 :
1009 8339 : att->atttypmod = typmod;
1010 :
1011 8339 : att->attnum = attributeNumber;
1012 8339 : att->attndims = attdim;
1013 :
1014 8339 : att->attnotnull = false;
1015 8339 : att->atthasdef = false;
1016 8339 : att->atthasmissing = false;
1017 8339 : att->attidentity = '\0';
1018 8339 : att->attgenerated = '\0';
1019 8339 : att->attisdropped = false;
1020 8339 : att->attislocal = true;
1021 8339 : att->attinhcount = 0;
1022 : /* variable-length fields are not present in tupledescs */
1023 :
1024 8339 : att->atttypid = oidtypeid;
1025 :
1026 : /*
1027 : * Our goal here is to support just enough types to let basic builtin
1028 : * commands work without catalog access - e.g. so that we can do certain
1029 : * things even in processes that are not connected to a database.
1030 : */
1031 8339 : switch (oidtypeid)
1032 : {
1033 6796 : case TEXTOID:
1034 : case TEXTARRAYOID:
1035 6796 : att->attlen = -1;
1036 6796 : att->attbyval = false;
1037 6796 : att->attalign = TYPALIGN_INT;
1038 6796 : att->attstorage = TYPSTORAGE_EXTENDED;
1039 6796 : att->attcompression = InvalidCompressionMethod;
1040 6796 : att->attcollation = DEFAULT_COLLATION_OID;
1041 6796 : break;
1042 :
1043 0 : case BOOLOID:
1044 0 : att->attlen = 1;
1045 0 : att->attbyval = true;
1046 0 : att->attalign = TYPALIGN_CHAR;
1047 0 : att->attstorage = TYPSTORAGE_PLAIN;
1048 0 : att->attcompression = InvalidCompressionMethod;
1049 0 : att->attcollation = InvalidOid;
1050 0 : break;
1051 :
1052 0 : case INT4OID:
1053 0 : att->attlen = 4;
1054 0 : att->attbyval = true;
1055 0 : att->attalign = TYPALIGN_INT;
1056 0 : att->attstorage = TYPSTORAGE_PLAIN;
1057 0 : att->attcompression = InvalidCompressionMethod;
1058 0 : att->attcollation = InvalidOid;
1059 0 : break;
1060 :
1061 1366 : case INT8OID:
1062 1366 : att->attlen = 8;
1063 1366 : att->attbyval = true;
1064 1366 : att->attalign = TYPALIGN_DOUBLE;
1065 1366 : att->attstorage = TYPSTORAGE_PLAIN;
1066 1366 : att->attcompression = InvalidCompressionMethod;
1067 1366 : att->attcollation = InvalidOid;
1068 1366 : break;
1069 :
1070 177 : case OIDOID:
1071 177 : att->attlen = 4;
1072 177 : att->attbyval = true;
1073 177 : att->attalign = TYPALIGN_INT;
1074 177 : att->attstorage = TYPSTORAGE_PLAIN;
1075 177 : att->attcompression = InvalidCompressionMethod;
1076 177 : att->attcollation = InvalidOid;
1077 177 : break;
1078 :
1079 0 : default:
1080 0 : elog(ERROR, "unsupported type %u", oidtypeid);
1081 : }
1082 :
1083 8339 : populate_compact_attribute(desc, attributeNumber - 1);
1084 8339 : }
1085 :
1086 : /*
1087 : * TupleDescInitEntryCollation
1088 : *
1089 : * Assign a nondefault collation to a previously initialized tuple descriptor
1090 : * entry.
1091 : */
1092 : void
1093 4250500 : TupleDescInitEntryCollation(TupleDesc desc,
1094 : AttrNumber attributeNumber,
1095 : Oid collationid)
1096 : {
1097 : /*
1098 : * sanity checks
1099 : */
1100 : Assert(desc);
1101 : Assert(attributeNumber >= 1);
1102 : Assert(attributeNumber <= desc->natts);
1103 :
1104 4250500 : TupleDescAttr(desc, attributeNumber - 1)->attcollation = collationid;
1105 4250500 : }
1106 :
1107 : /*
1108 : * BuildDescFromLists
1109 : *
1110 : * Build a TupleDesc given lists of column names (as String nodes),
1111 : * column type OIDs, typmods, and collation OIDs.
1112 : *
1113 : * No constraints are generated.
1114 : *
1115 : * This is for use with functions returning RECORD.
1116 : */
1117 : TupleDesc
1118 904 : BuildDescFromLists(const List *names, const List *types, const List *typmods, const List *collations)
1119 : {
1120 : int natts;
1121 : AttrNumber attnum;
1122 : ListCell *l1;
1123 : ListCell *l2;
1124 : ListCell *l3;
1125 : ListCell *l4;
1126 : TupleDesc desc;
1127 :
1128 904 : natts = list_length(names);
1129 : Assert(natts == list_length(types));
1130 : Assert(natts == list_length(typmods));
1131 : Assert(natts == list_length(collations));
1132 :
1133 : /*
1134 : * allocate a new tuple descriptor
1135 : */
1136 904 : desc = CreateTemplateTupleDesc(natts);
1137 :
1138 904 : attnum = 0;
1139 3169 : forfour(l1, names, l2, types, l3, typmods, l4, collations)
1140 : {
1141 2265 : char *attname = strVal(lfirst(l1));
1142 2265 : Oid atttypid = lfirst_oid(l2);
1143 2265 : int32 atttypmod = lfirst_int(l3);
1144 2265 : Oid attcollation = lfirst_oid(l4);
1145 :
1146 2265 : attnum++;
1147 :
1148 2265 : TupleDescInitEntry(desc, attnum, attname, atttypid, atttypmod, 0);
1149 2265 : TupleDescInitEntryCollation(desc, attnum, attcollation);
1150 : }
1151 :
1152 904 : TupleDescFinalize(desc);
1153 :
1154 904 : return desc;
1155 : }
1156 :
1157 : /*
1158 : * Get default expression (or NULL if none) for the given attribute number.
1159 : */
1160 : Node *
1161 78729 : TupleDescGetDefault(TupleDesc tupdesc, AttrNumber attnum)
1162 : {
1163 78729 : Node *result = NULL;
1164 :
1165 78729 : if (tupdesc->constr)
1166 : {
1167 78729 : AttrDefault *attrdef = tupdesc->constr->defval;
1168 :
1169 119064 : for (int i = 0; i < tupdesc->constr->num_defval; i++)
1170 : {
1171 119064 : if (attrdef[i].adnum == attnum)
1172 : {
1173 78729 : result = stringToNode(attrdef[i].adbin);
1174 78729 : break;
1175 : }
1176 : }
1177 : }
1178 :
1179 78729 : return result;
1180 : }
1181 :
1182 : /* ResourceOwner callbacks */
1183 :
1184 : static void
1185 11792 : ResOwnerReleaseTupleDesc(Datum res)
1186 : {
1187 11792 : TupleDesc tupdesc = (TupleDesc) DatumGetPointer(res);
1188 :
1189 : /* Like DecrTupleDescRefCount, but don't call ResourceOwnerForget() */
1190 : Assert(tupdesc->tdrefcount > 0);
1191 11792 : if (--tupdesc->tdrefcount == 0)
1192 395 : FreeTupleDesc(tupdesc);
1193 11792 : }
1194 :
1195 : static char *
1196 0 : ResOwnerPrintTupleDesc(Datum res)
1197 : {
1198 0 : TupleDesc tupdesc = (TupleDesc) DatumGetPointer(res);
1199 :
1200 0 : return psprintf("TupleDesc %p (%u,%d)",
1201 : tupdesc, tupdesc->tdtypeid, tupdesc->tdtypmod);
1202 : }
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