PostgreSQL Source Code  git master
parse_coerce.c
Go to the documentation of this file.
1 /*-------------------------------------------------------------------------
2  *
3  * parse_coerce.c
4  * handle type coercions/conversions for parser
5  *
6  * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/parser/parse_coerce.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "access/htup_details.h"
18 #include "catalog/pg_cast.h"
19 #include "catalog/pg_class.h"
20 #include "catalog/pg_inherits.h"
21 #include "catalog/pg_proc.h"
22 #include "catalog/pg_type.h"
23 #include "nodes/makefuncs.h"
24 #include "nodes/nodeFuncs.h"
25 #include "parser/parse_coerce.h"
26 #include "parser/parse_relation.h"
27 #include "parser/parse_type.h"
28 #include "utils/builtins.h"
29 #include "utils/datum.h"
30 #include "utils/lsyscache.h"
31 #include "utils/syscache.h"
32 #include "utils/typcache.h"
33 
34 
35 static Node *coerce_type_typmod(Node *node,
36  Oid targetTypeId, int32 targetTypMod,
37  CoercionContext ccontext, CoercionForm cformat,
38  int location,
39  bool hideInputCoercion);
40 static void hide_coercion_node(Node *node);
41 static Node *build_coercion_expression(Node *node,
42  CoercionPathType pathtype,
43  Oid funcId,
44  Oid targetTypeId, int32 targetTypMod,
45  CoercionContext ccontext, CoercionForm cformat,
46  int location);
47 static Node *coerce_record_to_complex(ParseState *pstate, Node *node,
48  Oid targetTypeId,
49  CoercionContext ccontext,
50  CoercionForm cformat,
51  int location);
52 static bool is_complex_array(Oid typid);
53 static bool typeIsOfTypedTable(Oid reltypeId, Oid reloftypeId);
54 
55 
56 /*
57  * coerce_to_target_type()
58  * Convert an expression to a target type and typmod.
59  *
60  * This is the general-purpose entry point for arbitrary type coercion
61  * operations. Direct use of the component operations can_coerce_type,
62  * coerce_type, and coerce_type_typmod should be restricted to special
63  * cases (eg, when the conversion is expected to succeed).
64  *
65  * Returns the possibly-transformed expression tree, or NULL if the type
66  * conversion is not possible. (We do this, rather than ereport'ing directly,
67  * so that callers can generate custom error messages indicating context.)
68  *
69  * pstate - parse state (can be NULL, see coerce_type)
70  * expr - input expression tree (already transformed by transformExpr)
71  * exprtype - result type of expr
72  * targettype - desired result type
73  * targettypmod - desired result typmod
74  * ccontext, cformat - context indicators to control coercions
75  * location - parse location of the coercion request, or -1 if unknown/implicit
76  */
77 Node *
78 coerce_to_target_type(ParseState *pstate, Node *expr, Oid exprtype,
79  Oid targettype, int32 targettypmod,
80  CoercionContext ccontext,
81  CoercionForm cformat,
82  int location)
83 {
84  Node *result;
85  Node *origexpr;
86 
87  if (!can_coerce_type(1, &exprtype, &targettype, ccontext))
88  return NULL;
89 
90  /*
91  * If the input has a CollateExpr at the top, strip it off, perform the
92  * coercion, and put a new one back on. This is annoying since it
93  * duplicates logic in coerce_type, but if we don't do this then it's too
94  * hard to tell whether coerce_type actually changed anything, and we
95  * *must* know that to avoid possibly calling hide_coercion_node on
96  * something that wasn't generated by coerce_type. Note that if there are
97  * multiple stacked CollateExprs, we just discard all but the topmost.
98  */
99  origexpr = expr;
100  while (expr && IsA(expr, CollateExpr))
101  expr = (Node *) ((CollateExpr *) expr)->arg;
102 
103  result = coerce_type(pstate, expr, exprtype,
104  targettype, targettypmod,
105  ccontext, cformat, location);
106 
107  /*
108  * If the target is a fixed-length type, it may need a length coercion as
109  * well as a type coercion. If we find ourselves adding both, force the
110  * inner coercion node to implicit display form.
111  */
112  result = coerce_type_typmod(result,
113  targettype, targettypmod,
114  ccontext, cformat, location,
115  (result != expr && !IsA(result, Const)));
116 
117  if (expr != origexpr)
118  {
119  /* Reinstall top CollateExpr */
120  CollateExpr *coll = (CollateExpr *) origexpr;
121  CollateExpr *newcoll = makeNode(CollateExpr);
122 
123  newcoll->arg = (Expr *) result;
124  newcoll->collOid = coll->collOid;
125  newcoll->location = coll->location;
126  result = (Node *) newcoll;
127  }
128 
129  return result;
130 }
131 
132 
133 /*
134  * coerce_type()
135  * Convert an expression to a different type.
136  *
137  * The caller should already have determined that the coercion is possible;
138  * see can_coerce_type.
139  *
140  * Normally, no coercion to a typmod (length) is performed here. The caller
141  * must call coerce_type_typmod as well, if a typmod constraint is wanted.
142  * (But if the target type is a domain, it may internally contain a
143  * typmod constraint, which will be applied inside coerce_to_domain.)
144  * In some cases pg_cast specifies a type coercion function that also
145  * applies length conversion, and in those cases only, the result will
146  * already be properly coerced to the specified typmod.
147  *
148  * pstate is only used in the case that we are able to resolve the type of
149  * a previously UNKNOWN Param. It is okay to pass pstate = NULL if the
150  * caller does not want type information updated for Params.
151  *
152  * Note: this function must not modify the given expression tree, only add
153  * decoration on top of it. See transformSetOperationTree, for example.
154  */
155 Node *
156 coerce_type(ParseState *pstate, Node *node,
157  Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod,
158  CoercionContext ccontext, CoercionForm cformat, int location)
159 {
160  Node *result;
161  CoercionPathType pathtype;
162  Oid funcId;
163 
164  if (targetTypeId == inputTypeId ||
165  node == NULL)
166  {
167  /* no conversion needed */
168  return node;
169  }
170  if (targetTypeId == ANYOID ||
171  targetTypeId == ANYELEMENTOID ||
172  targetTypeId == ANYNONARRAYOID)
173  {
174  /*
175  * Assume can_coerce_type verified that implicit coercion is okay.
176  *
177  * Note: by returning the unmodified node here, we are saying that
178  * it's OK to treat an UNKNOWN constant as a valid input for a
179  * function accepting ANY, ANYELEMENT, or ANYNONARRAY. This should be
180  * all right, since an UNKNOWN value is still a perfectly valid Datum.
181  *
182  * NB: we do NOT want a RelabelType here: the exposed type of the
183  * function argument must be its actual type, not the polymorphic
184  * pseudotype.
185  */
186  return node;
187  }
188  if (targetTypeId == ANYARRAYOID ||
189  targetTypeId == ANYENUMOID ||
190  targetTypeId == ANYRANGEOID)
191  {
192  /*
193  * Assume can_coerce_type verified that implicit coercion is okay.
194  *
195  * These cases are unlike the ones above because the exposed type of
196  * the argument must be an actual array, enum, or range type. In
197  * particular the argument must *not* be an UNKNOWN constant. If it
198  * is, we just fall through; below, we'll call anyarray_in,
199  * anyenum_in, or anyrange_in, which will produce an error. Also, if
200  * what we have is a domain over array, enum, or range, we have to
201  * relabel it to its base type.
202  *
203  * Note: currently, we can't actually see a domain-over-enum here,
204  * since the other functions in this file will not match such a
205  * parameter to ANYENUM. But that should get changed eventually.
206  */
207  if (inputTypeId != UNKNOWNOID)
208  {
209  Oid baseTypeId = getBaseType(inputTypeId);
210 
211  if (baseTypeId != inputTypeId)
212  {
213  RelabelType *r = makeRelabelType((Expr *) node,
214  baseTypeId, -1,
215  InvalidOid,
216  cformat);
217 
218  r->location = location;
219  return (Node *) r;
220  }
221  /* Not a domain type, so return it as-is */
222  return node;
223  }
224  }
225  if (inputTypeId == UNKNOWNOID && IsA(node, Const))
226  {
227  /*
228  * Input is a string constant with previously undetermined type. Apply
229  * the target type's typinput function to it to produce a constant of
230  * the target type.
231  *
232  * NOTE: this case cannot be folded together with the other
233  * constant-input case, since the typinput function does not
234  * necessarily behave the same as a type conversion function. For
235  * example, int4's typinput function will reject "1.2", whereas
236  * float-to-int type conversion will round to integer.
237  *
238  * XXX if the typinput function is not immutable, we really ought to
239  * postpone evaluation of the function call until runtime. But there
240  * is no way to represent a typinput function call as an expression
241  * tree, because C-string values are not Datums. (XXX This *is*
242  * possible as of 7.3, do we want to do it?)
243  */
244  Const *con = (Const *) node;
245  Const *newcon = makeNode(Const);
246  Oid baseTypeId;
247  int32 baseTypeMod;
248  int32 inputTypeMod;
249  Type baseType;
250  ParseCallbackState pcbstate;
251 
252  /*
253  * If the target type is a domain, we want to call its base type's
254  * input routine, not domain_in(). This is to avoid premature failure
255  * when the domain applies a typmod: existing input routines follow
256  * implicit-coercion semantics for length checks, which is not always
257  * what we want here. The needed check will be applied properly
258  * inside coerce_to_domain().
259  */
260  baseTypeMod = targetTypeMod;
261  baseTypeId = getBaseTypeAndTypmod(targetTypeId, &baseTypeMod);
262 
263  /*
264  * For most types we pass typmod -1 to the input routine, because
265  * existing input routines follow implicit-coercion semantics for
266  * length checks, which is not always what we want here. Any length
267  * constraint will be applied later by our caller. An exception
268  * however is the INTERVAL type, for which we *must* pass the typmod
269  * or it won't be able to obey the bizarre SQL-spec input rules. (Ugly
270  * as sin, but so is this part of the spec...)
271  */
272  if (baseTypeId == INTERVALOID)
273  inputTypeMod = baseTypeMod;
274  else
275  inputTypeMod = -1;
276 
277  baseType = typeidType(baseTypeId);
278 
279  newcon->consttype = baseTypeId;
280  newcon->consttypmod = inputTypeMod;
281  newcon->constcollid = typeTypeCollation(baseType);
282  newcon->constlen = typeLen(baseType);
283  newcon->constbyval = typeByVal(baseType);
284  newcon->constisnull = con->constisnull;
285 
286  /*
287  * We use the original literal's location regardless of the position
288  * of the coercion. This is a change from pre-9.2 behavior, meant to
289  * simplify life for pg_stat_statements.
290  */
291  newcon->location = con->location;
292 
293  /*
294  * Set up to point at the constant's text if the input routine throws
295  * an error.
296  */
297  setup_parser_errposition_callback(&pcbstate, pstate, con->location);
298 
299  /*
300  * We assume here that UNKNOWN's internal representation is the same
301  * as CSTRING.
302  */
303  if (!con->constisnull)
304  newcon->constvalue = stringTypeDatum(baseType,
306  inputTypeMod);
307  else
308  newcon->constvalue = stringTypeDatum(baseType,
309  NULL,
310  inputTypeMod);
311 
312  /*
313  * If it's a varlena value, force it to be in non-expanded
314  * (non-toasted) format; this avoids any possible dependency on
315  * external values and improves consistency of representation.
316  */
317  if (!con->constisnull && newcon->constlen == -1)
318  newcon->constvalue =
320 
321 #ifdef RANDOMIZE_ALLOCATED_MEMORY
322 
323  /*
324  * For pass-by-reference data types, repeat the conversion to see if
325  * the input function leaves any uninitialized bytes in the result. We
326  * can only detect that reliably if RANDOMIZE_ALLOCATED_MEMORY is
327  * enabled, so we don't bother testing otherwise. The reason we don't
328  * want any instability in the input function is that comparison of
329  * Const nodes relies on bytewise comparison of the datums, so if the
330  * input function leaves garbage then subexpressions that should be
331  * identical may not get recognized as such. See pgsql-hackers
332  * discussion of 2008-04-04.
333  */
334  if (!con->constisnull && !newcon->constbyval)
335  {
336  Datum val2;
337 
338  val2 = stringTypeDatum(baseType,
340  inputTypeMod);
341  if (newcon->constlen == -1)
342  val2 = PointerGetDatum(PG_DETOAST_DATUM(val2));
343  if (!datumIsEqual(newcon->constvalue, val2, false, newcon->constlen))
344  elog(WARNING, "type %s has unstable input conversion for \"%s\"",
345  typeTypeName(baseType), DatumGetCString(con->constvalue));
346  }
347 #endif
348 
350 
351  result = (Node *) newcon;
352 
353  /* If target is a domain, apply constraints. */
354  if (baseTypeId != targetTypeId)
355  result = coerce_to_domain(result,
356  baseTypeId, baseTypeMod,
357  targetTypeId,
358  ccontext, cformat, location,
359  false);
360 
361  ReleaseSysCache(baseType);
362 
363  return result;
364  }
365  if (IsA(node, Param) &&
366  pstate != NULL && pstate->p_coerce_param_hook != NULL)
367  {
368  /*
369  * Allow the CoerceParamHook to decide what happens. It can return a
370  * transformed node (very possibly the same Param node), or return
371  * NULL to indicate we should proceed with normal coercion.
372  */
373  result = pstate->p_coerce_param_hook(pstate,
374  (Param *) node,
375  targetTypeId,
376  targetTypeMod,
377  location);
378  if (result)
379  return result;
380  }
381  if (IsA(node, CollateExpr))
382  {
383  /*
384  * If we have a COLLATE clause, we have to push the coercion
385  * underneath the COLLATE. This is really ugly, but there is little
386  * choice because the above hacks on Consts and Params wouldn't happen
387  * otherwise. This kluge has consequences in coerce_to_target_type.
388  */
389  CollateExpr *coll = (CollateExpr *) node;
390  CollateExpr *newcoll = makeNode(CollateExpr);
391 
392  newcoll->arg = (Expr *)
393  coerce_type(pstate, (Node *) coll->arg,
394  inputTypeId, targetTypeId, targetTypeMod,
395  ccontext, cformat, location);
396  newcoll->collOid = coll->collOid;
397  newcoll->location = coll->location;
398  return (Node *) newcoll;
399  }
400  pathtype = find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
401  &funcId);
402  if (pathtype != COERCION_PATH_NONE)
403  {
404  if (pathtype != COERCION_PATH_RELABELTYPE)
405  {
406  /*
407  * Generate an expression tree representing run-time application
408  * of the conversion function. If we are dealing with a domain
409  * target type, the conversion function will yield the base type,
410  * and we need to extract the correct typmod to use from the
411  * domain's typtypmod.
412  */
413  Oid baseTypeId;
414  int32 baseTypeMod;
415 
416  baseTypeMod = targetTypeMod;
417  baseTypeId = getBaseTypeAndTypmod(targetTypeId, &baseTypeMod);
418 
419  result = build_coercion_expression(node, pathtype, funcId,
420  baseTypeId, baseTypeMod,
421  ccontext, cformat, location);
422 
423  /*
424  * If domain, coerce to the domain type and relabel with domain
425  * type ID, hiding the previous coercion node.
426  */
427  if (targetTypeId != baseTypeId)
428  result = coerce_to_domain(result, baseTypeId, baseTypeMod,
429  targetTypeId,
430  ccontext, cformat, location,
431  true);
432  }
433  else
434  {
435  /*
436  * We don't need to do a physical conversion, but we do need to
437  * attach a RelabelType node so that the expression will be seen
438  * to have the intended type when inspected by higher-level code.
439  *
440  * Also, domains may have value restrictions beyond the base type
441  * that must be accounted for. If the destination is a domain
442  * then we won't need a RelabelType node.
443  */
444  result = coerce_to_domain(node, InvalidOid, -1, targetTypeId,
445  ccontext, cformat, location,
446  false);
447  if (result == node)
448  {
449  /*
450  * XXX could we label result with exprTypmod(node) instead of
451  * default -1 typmod, to save a possible length-coercion
452  * later? Would work if both types have same interpretation of
453  * typmod, which is likely but not certain.
454  */
455  RelabelType *r = makeRelabelType((Expr *) result,
456  targetTypeId, -1,
457  InvalidOid,
458  cformat);
459 
460  r->location = location;
461  result = (Node *) r;
462  }
463  }
464  return result;
465  }
466  if (inputTypeId == RECORDOID &&
467  ISCOMPLEX(targetTypeId))
468  {
469  /* Coerce a RECORD to a specific complex type */
470  return coerce_record_to_complex(pstate, node, targetTypeId,
471  ccontext, cformat, location);
472  }
473  if (targetTypeId == RECORDOID &&
474  ISCOMPLEX(inputTypeId))
475  {
476  /* Coerce a specific complex type to RECORD */
477  /* NB: we do NOT want a RelabelType here */
478  return node;
479  }
480 #ifdef NOT_USED
481  if (inputTypeId == RECORDARRAYOID &&
482  is_complex_array(targetTypeId))
483  {
484  /* Coerce record[] to a specific complex array type */
485  /* not implemented yet ... */
486  }
487 #endif
488  if (targetTypeId == RECORDARRAYOID &&
489  is_complex_array(inputTypeId))
490  {
491  /* Coerce a specific complex array type to record[] */
492  /* NB: we do NOT want a RelabelType here */
493  return node;
494  }
495  if (typeInheritsFrom(inputTypeId, targetTypeId)
496  || typeIsOfTypedTable(inputTypeId, targetTypeId))
497  {
498  /*
499  * Input class type is a subclass of target, so generate an
500  * appropriate runtime conversion (removing unneeded columns and
501  * possibly rearranging the ones that are wanted).
502  *
503  * We will also get here when the input is a domain over a subclass of
504  * the target type. To keep life simple for the executor, we define
505  * ConvertRowtypeExpr as only working between regular composite types;
506  * therefore, in such cases insert a RelabelType to smash the input
507  * expression down to its base type.
508  */
509  Oid baseTypeId = getBaseType(inputTypeId);
511 
512  if (baseTypeId != inputTypeId)
513  {
514  RelabelType *rt = makeRelabelType((Expr *) node,
515  baseTypeId, -1,
516  InvalidOid,
518 
519  rt->location = location;
520  node = (Node *) rt;
521  }
522  r->arg = (Expr *) node;
523  r->resulttype = targetTypeId;
524  r->convertformat = cformat;
525  r->location = location;
526  return (Node *) r;
527  }
528  /* If we get here, caller blew it */
529  elog(ERROR, "failed to find conversion function from %s to %s",
530  format_type_be(inputTypeId), format_type_be(targetTypeId));
531  return NULL; /* keep compiler quiet */
532 }
533 
534 
535 /*
536  * can_coerce_type()
537  * Can input_typeids be coerced to target_typeids?
538  *
539  * We must be told the context (CAST construct, assignment, implicit coercion)
540  * as this determines the set of available casts.
541  */
542 bool
543 can_coerce_type(int nargs, Oid *input_typeids, Oid *target_typeids,
544  CoercionContext ccontext)
545 {
546  bool have_generics = false;
547  int i;
548 
549  /* run through argument list... */
550  for (i = 0; i < nargs; i++)
551  {
552  Oid inputTypeId = input_typeids[i];
553  Oid targetTypeId = target_typeids[i];
554  CoercionPathType pathtype;
555  Oid funcId;
556 
557  /* no problem if same type */
558  if (inputTypeId == targetTypeId)
559  continue;
560 
561  /* accept if target is ANY */
562  if (targetTypeId == ANYOID)
563  continue;
564 
565  /* accept if target is polymorphic, for now */
566  if (IsPolymorphicType(targetTypeId))
567  {
568  have_generics = true; /* do more checking later */
569  continue;
570  }
571 
572  /*
573  * If input is an untyped string constant, assume we can convert it to
574  * anything.
575  */
576  if (inputTypeId == UNKNOWNOID)
577  continue;
578 
579  /*
580  * If pg_cast shows that we can coerce, accept. This test now covers
581  * both binary-compatible and coercion-function cases.
582  */
583  pathtype = find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
584  &funcId);
585  if (pathtype != COERCION_PATH_NONE)
586  continue;
587 
588  /*
589  * If input is RECORD and target is a composite type, assume we can
590  * coerce (may need tighter checking here)
591  */
592  if (inputTypeId == RECORDOID &&
593  ISCOMPLEX(targetTypeId))
594  continue;
595 
596  /*
597  * If input is a composite type and target is RECORD, accept
598  */
599  if (targetTypeId == RECORDOID &&
600  ISCOMPLEX(inputTypeId))
601  continue;
602 
603 #ifdef NOT_USED /* not implemented yet */
604 
605  /*
606  * If input is record[] and target is a composite array type, assume
607  * we can coerce (may need tighter checking here)
608  */
609  if (inputTypeId == RECORDARRAYOID &&
610  is_complex_array(targetTypeId))
611  continue;
612 #endif
613 
614  /*
615  * If input is a composite array type and target is record[], accept
616  */
617  if (targetTypeId == RECORDARRAYOID &&
618  is_complex_array(inputTypeId))
619  continue;
620 
621  /*
622  * If input is a class type that inherits from target, accept
623  */
624  if (typeInheritsFrom(inputTypeId, targetTypeId)
625  || typeIsOfTypedTable(inputTypeId, targetTypeId))
626  continue;
627 
628  /*
629  * Else, cannot coerce at this argument position
630  */
631  return false;
632  }
633 
634  /* If we found any generic argument types, cross-check them */
635  if (have_generics)
636  {
637  if (!check_generic_type_consistency(input_typeids, target_typeids,
638  nargs))
639  return false;
640  }
641 
642  return true;
643 }
644 
645 
646 /*
647  * Create an expression tree to represent coercion to a domain type.
648  *
649  * 'arg': input expression
650  * 'baseTypeId': base type of domain, if known (pass InvalidOid if caller
651  * has not bothered to look this up)
652  * 'baseTypeMod': base type typmod of domain, if known (pass -1 if caller
653  * has not bothered to look this up)
654  * 'typeId': target type to coerce to
655  * 'ccontext': context indicator to control coercions
656  * 'cformat': coercion display format
657  * 'location': coercion request location
658  * 'hideInputCoercion': if true, hide the input coercion under this one.
659  *
660  * If the target type isn't a domain, the given 'arg' is returned as-is.
661  */
662 Node *
663 coerce_to_domain(Node *arg, Oid baseTypeId, int32 baseTypeMod, Oid typeId,
664  CoercionContext ccontext, CoercionForm cformat, int location,
665  bool hideInputCoercion)
666 {
667  CoerceToDomain *result;
668 
669  /* Get the base type if it hasn't been supplied */
670  if (baseTypeId == InvalidOid)
671  baseTypeId = getBaseTypeAndTypmod(typeId, &baseTypeMod);
672 
673  /* If it isn't a domain, return the node as it was passed in */
674  if (baseTypeId == typeId)
675  return arg;
676 
677  /* Suppress display of nested coercion steps */
678  if (hideInputCoercion)
679  hide_coercion_node(arg);
680 
681  /*
682  * If the domain applies a typmod to its base type, build the appropriate
683  * coercion step. Mark it implicit for display purposes, because we don't
684  * want it shown separately by ruleutils.c; but the isExplicit flag passed
685  * to the conversion function depends on the manner in which the domain
686  * coercion is invoked, so that the semantics of implicit and explicit
687  * coercion differ. (Is that really the behavior we want?)
688  *
689  * NOTE: because we apply this as part of the fixed expression structure,
690  * ALTER DOMAIN cannot alter the typtypmod. But it's unclear that that
691  * would be safe to do anyway, without lots of knowledge about what the
692  * base type thinks the typmod means.
693  */
694  arg = coerce_type_typmod(arg, baseTypeId, baseTypeMod,
695  ccontext, COERCE_IMPLICIT_CAST, location,
696  false);
697 
698  /*
699  * Now build the domain coercion node. This represents run-time checking
700  * of any constraints currently attached to the domain. This also ensures
701  * that the expression is properly labeled as to result type.
702  */
703  result = makeNode(CoerceToDomain);
704  result->arg = (Expr *) arg;
705  result->resulttype = typeId;
706  result->resulttypmod = -1; /* currently, always -1 for domains */
707  /* resultcollid will be set by parse_collate.c */
708  result->coercionformat = cformat;
709  result->location = location;
710 
711  return (Node *) result;
712 }
713 
714 
715 /*
716  * coerce_type_typmod()
717  * Force a value to a particular typmod, if meaningful and possible.
718  *
719  * This is applied to values that are going to be stored in a relation
720  * (where we have an atttypmod for the column) as well as values being
721  * explicitly CASTed (where the typmod comes from the target type spec).
722  *
723  * The caller must have already ensured that the value is of the correct
724  * type, typically by applying coerce_type.
725  *
726  * ccontext may affect semantics, depending on whether the length coercion
727  * function pays attention to the isExplicit flag it's passed.
728  *
729  * cformat determines the display properties of the generated node (if any).
730  *
731  * If hideInputCoercion is true *and* we generate a node, the input node is
732  * forced to IMPLICIT display form, so that only the typmod coercion node will
733  * be visible when displaying the expression.
734  *
735  * NOTE: this does not need to work on domain types, because any typmod
736  * coercion for a domain is considered to be part of the type coercion
737  * needed to produce the domain value in the first place. So, no getBaseType.
738  */
739 static Node *
740 coerce_type_typmod(Node *node, Oid targetTypeId, int32 targetTypMod,
741  CoercionContext ccontext, CoercionForm cformat,
742  int location,
743  bool hideInputCoercion)
744 {
745  CoercionPathType pathtype;
746  Oid funcId;
747 
748  /*
749  * A negative typmod is assumed to mean that no coercion is wanted. Also,
750  * skip coercion if already done.
751  */
752  if (targetTypMod < 0 || targetTypMod == exprTypmod(node))
753  return node;
754 
755  pathtype = find_typmod_coercion_function(targetTypeId, &funcId);
756 
757  if (pathtype != COERCION_PATH_NONE)
758  {
759  /* Suppress display of nested coercion steps */
760  if (hideInputCoercion)
761  hide_coercion_node(node);
762 
763  node = build_coercion_expression(node, pathtype, funcId,
764  targetTypeId, targetTypMod,
765  ccontext, cformat, location);
766  }
767 
768  return node;
769 }
770 
771 /*
772  * Mark a coercion node as IMPLICIT so it will never be displayed by
773  * ruleutils.c. We use this when we generate a nest of coercion nodes
774  * to implement what is logically one conversion; the inner nodes are
775  * forced to IMPLICIT_CAST format. This does not change their semantics,
776  * only display behavior.
777  *
778  * It is caller error to call this on something that doesn't have a
779  * CoercionForm field.
780  */
781 static void
783 {
784  if (IsA(node, FuncExpr))
785  ((FuncExpr *) node)->funcformat = COERCE_IMPLICIT_CAST;
786  else if (IsA(node, RelabelType))
787  ((RelabelType *) node)->relabelformat = COERCE_IMPLICIT_CAST;
788  else if (IsA(node, CoerceViaIO))
789  ((CoerceViaIO *) node)->coerceformat = COERCE_IMPLICIT_CAST;
790  else if (IsA(node, ArrayCoerceExpr))
791  ((ArrayCoerceExpr *) node)->coerceformat = COERCE_IMPLICIT_CAST;
792  else if (IsA(node, ConvertRowtypeExpr))
793  ((ConvertRowtypeExpr *) node)->convertformat = COERCE_IMPLICIT_CAST;
794  else if (IsA(node, RowExpr))
795  ((RowExpr *) node)->row_format = COERCE_IMPLICIT_CAST;
796  else if (IsA(node, CoerceToDomain))
797  ((CoerceToDomain *) node)->coercionformat = COERCE_IMPLICIT_CAST;
798  else
799  elog(ERROR, "unsupported node type: %d", (int) nodeTag(node));
800 }
801 
802 /*
803  * build_coercion_expression()
804  * Construct an expression tree for applying a pg_cast entry.
805  *
806  * This is used for both type-coercion and length-coercion operations,
807  * since there is no difference in terms of the calling convention.
808  */
809 static Node *
811  CoercionPathType pathtype,
812  Oid funcId,
813  Oid targetTypeId, int32 targetTypMod,
814  CoercionContext ccontext, CoercionForm cformat,
815  int location)
816 {
817  int nargs = 0;
818 
819  if (OidIsValid(funcId))
820  {
821  HeapTuple tp;
822  Form_pg_proc procstruct;
823 
825  if (!HeapTupleIsValid(tp))
826  elog(ERROR, "cache lookup failed for function %u", funcId);
827  procstruct = (Form_pg_proc) GETSTRUCT(tp);
828 
829  /*
830  * These Asserts essentially check that function is a legal coercion
831  * function. We can't make the seemingly obvious tests on prorettype
832  * and proargtypes[0], even in the COERCION_PATH_FUNC case, because of
833  * various binary-compatibility cases.
834  */
835  /* Assert(targetTypeId == procstruct->prorettype); */
836  Assert(!procstruct->proretset);
837  Assert(procstruct->prokind == PROKIND_FUNCTION);
838  nargs = procstruct->pronargs;
839  Assert(nargs >= 1 && nargs <= 3);
840  /* Assert(procstruct->proargtypes.values[0] == exprType(node)); */
841  Assert(nargs < 2 || procstruct->proargtypes.values[1] == INT4OID);
842  Assert(nargs < 3 || procstruct->proargtypes.values[2] == BOOLOID);
843 
844  ReleaseSysCache(tp);
845  }
846 
847  if (pathtype == COERCION_PATH_FUNC)
848  {
849  /* We build an ordinary FuncExpr with special arguments */
850  FuncExpr *fexpr;
851  List *args;
852  Const *cons;
853 
854  Assert(OidIsValid(funcId));
855 
856  args = list_make1(node);
857 
858  if (nargs >= 2)
859  {
860  /* Pass target typmod as an int4 constant */
861  cons = makeConst(INT4OID,
862  -1,
863  InvalidOid,
864  sizeof(int32),
865  Int32GetDatum(targetTypMod),
866  false,
867  true);
868 
869  args = lappend(args, cons);
870  }
871 
872  if (nargs == 3)
873  {
874  /* Pass it a boolean isExplicit parameter, too */
875  cons = makeConst(BOOLOID,
876  -1,
877  InvalidOid,
878  sizeof(bool),
879  BoolGetDatum(ccontext == COERCION_EXPLICIT),
880  false,
881  true);
882 
883  args = lappend(args, cons);
884  }
885 
886  fexpr = makeFuncExpr(funcId, targetTypeId, args,
887  InvalidOid, InvalidOid, cformat);
888  fexpr->location = location;
889  return (Node *) fexpr;
890  }
891  else if (pathtype == COERCION_PATH_ARRAYCOERCE)
892  {
893  /* We need to build an ArrayCoerceExpr */
896  Oid sourceBaseTypeId;
897  int32 sourceBaseTypeMod;
898  Oid targetElementType;
899  Node *elemexpr;
900 
901  /*
902  * Look through any domain over the source array type. Note we don't
903  * expect that the target type is a domain; it must be a plain array.
904  * (To get to a domain target type, we'll do coerce_to_domain later.)
905  */
906  sourceBaseTypeMod = exprTypmod(node);
907  sourceBaseTypeId = getBaseTypeAndTypmod(exprType(node),
908  &sourceBaseTypeMod);
909 
910  /* Set up CaseTestExpr representing one element of source array */
911  ctest->typeId = get_element_type(sourceBaseTypeId);
912  Assert(OidIsValid(ctest->typeId));
913  ctest->typeMod = sourceBaseTypeMod;
914  ctest->collation = InvalidOid; /* Assume coercions don't care */
915 
916  /* And coerce it to the target element type */
917  targetElementType = get_element_type(targetTypeId);
918  Assert(OidIsValid(targetElementType));
919 
920  elemexpr = coerce_to_target_type(NULL,
921  (Node *) ctest,
922  ctest->typeId,
923  targetElementType,
924  targetTypMod,
925  ccontext,
926  cformat,
927  location);
928  if (elemexpr == NULL) /* shouldn't happen */
929  elog(ERROR, "failed to coerce array element type as expected");
930 
931  acoerce->arg = (Expr *) node;
932  acoerce->elemexpr = (Expr *) elemexpr;
933  acoerce->resulttype = targetTypeId;
934 
935  /*
936  * Label the output as having a particular element typmod only if we
937  * ended up with a per-element expression that is labeled that way.
938  */
939  acoerce->resulttypmod = exprTypmod(elemexpr);
940  /* resultcollid will be set by parse_collate.c */
941  acoerce->coerceformat = cformat;
942  acoerce->location = location;
943 
944  return (Node *) acoerce;
945  }
946  else if (pathtype == COERCION_PATH_COERCEVIAIO)
947  {
948  /* We need to build a CoerceViaIO node */
949  CoerceViaIO *iocoerce = makeNode(CoerceViaIO);
950 
951  Assert(!OidIsValid(funcId));
952 
953  iocoerce->arg = (Expr *) node;
954  iocoerce->resulttype = targetTypeId;
955  /* resultcollid will be set by parse_collate.c */
956  iocoerce->coerceformat = cformat;
957  iocoerce->location = location;
958 
959  return (Node *) iocoerce;
960  }
961  else
962  {
963  elog(ERROR, "unsupported pathtype %d in build_coercion_expression",
964  (int) pathtype);
965  return NULL; /* keep compiler quiet */
966  }
967 }
968 
969 
970 /*
971  * coerce_record_to_complex
972  * Coerce a RECORD to a specific composite type.
973  *
974  * Currently we only support this for inputs that are RowExprs or whole-row
975  * Vars.
976  */
977 static Node *
979  Oid targetTypeId,
980  CoercionContext ccontext,
981  CoercionForm cformat,
982  int location)
983 {
984  RowExpr *rowexpr;
985  Oid baseTypeId;
986  int32 baseTypeMod = -1;
987  TupleDesc tupdesc;
988  List *args = NIL;
989  List *newargs;
990  int i;
991  int ucolno;
992  ListCell *arg;
993 
994  if (node && IsA(node, RowExpr))
995  {
996  /*
997  * Since the RowExpr must be of type RECORD, we needn't worry about it
998  * containing any dropped columns.
999  */
1000  args = ((RowExpr *) node)->args;
1001  }
1002  else if (node && IsA(node, Var) &&
1003  ((Var *) node)->varattno == InvalidAttrNumber)
1004  {
1005  int rtindex = ((Var *) node)->varno;
1006  int sublevels_up = ((Var *) node)->varlevelsup;
1007  int vlocation = ((Var *) node)->location;
1008  RangeTblEntry *rte;
1009 
1010  rte = GetRTEByRangeTablePosn(pstate, rtindex, sublevels_up);
1011  expandRTE(rte, rtindex, sublevels_up, vlocation, false,
1012  NULL, &args);
1013  }
1014  else
1015  ereport(ERROR,
1016  (errcode(ERRCODE_CANNOT_COERCE),
1017  errmsg("cannot cast type %s to %s",
1018  format_type_be(RECORDOID),
1019  format_type_be(targetTypeId)),
1020  parser_coercion_errposition(pstate, location, node)));
1021 
1022  /*
1023  * Look up the composite type, accounting for possibility that what we are
1024  * given is a domain over composite.
1025  */
1026  baseTypeId = getBaseTypeAndTypmod(targetTypeId, &baseTypeMod);
1027  tupdesc = lookup_rowtype_tupdesc(baseTypeId, baseTypeMod);
1028 
1029  /* Process the fields */
1030  newargs = NIL;
1031  ucolno = 1;
1032  arg = list_head(args);
1033  for (i = 0; i < tupdesc->natts; i++)
1034  {
1035  Node *expr;
1036  Node *cexpr;
1037  Oid exprtype;
1038  Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
1039 
1040  /* Fill in NULLs for dropped columns in rowtype */
1041  if (attr->attisdropped)
1042  {
1043  /*
1044  * can't use atttypid here, but it doesn't really matter what type
1045  * the Const claims to be.
1046  */
1047  newargs = lappend(newargs,
1048  makeNullConst(INT4OID, -1, InvalidOid));
1049  continue;
1050  }
1051 
1052  if (arg == NULL)
1053  ereport(ERROR,
1054  (errcode(ERRCODE_CANNOT_COERCE),
1055  errmsg("cannot cast type %s to %s",
1056  format_type_be(RECORDOID),
1057  format_type_be(targetTypeId)),
1058  errdetail("Input has too few columns."),
1059  parser_coercion_errposition(pstate, location, node)));
1060  expr = (Node *) lfirst(arg);
1061  exprtype = exprType(expr);
1062 
1063  cexpr = coerce_to_target_type(pstate,
1064  expr, exprtype,
1065  attr->atttypid,
1066  attr->atttypmod,
1067  ccontext,
1069  -1);
1070  if (cexpr == NULL)
1071  ereport(ERROR,
1072  (errcode(ERRCODE_CANNOT_COERCE),
1073  errmsg("cannot cast type %s to %s",
1074  format_type_be(RECORDOID),
1075  format_type_be(targetTypeId)),
1076  errdetail("Cannot cast type %s to %s in column %d.",
1077  format_type_be(exprtype),
1078  format_type_be(attr->atttypid),
1079  ucolno),
1080  parser_coercion_errposition(pstate, location, expr)));
1081  newargs = lappend(newargs, cexpr);
1082  ucolno++;
1083  arg = lnext(arg);
1084  }
1085  if (arg != NULL)
1086  ereport(ERROR,
1087  (errcode(ERRCODE_CANNOT_COERCE),
1088  errmsg("cannot cast type %s to %s",
1089  format_type_be(RECORDOID),
1090  format_type_be(targetTypeId)),
1091  errdetail("Input has too many columns."),
1092  parser_coercion_errposition(pstate, location, node)));
1093 
1094  ReleaseTupleDesc(tupdesc);
1095 
1096  rowexpr = makeNode(RowExpr);
1097  rowexpr->args = newargs;
1098  rowexpr->row_typeid = baseTypeId;
1099  rowexpr->row_format = cformat;
1100  rowexpr->colnames = NIL; /* not needed for named target type */
1101  rowexpr->location = location;
1102 
1103  /* If target is a domain, apply constraints */
1104  if (baseTypeId != targetTypeId)
1105  {
1106  rowexpr->row_format = COERCE_IMPLICIT_CAST;
1107  return coerce_to_domain((Node *) rowexpr,
1108  baseTypeId, baseTypeMod,
1109  targetTypeId,
1110  ccontext, cformat, location,
1111  false);
1112  }
1113 
1114  return (Node *) rowexpr;
1115 }
1116 
1117 /*
1118  * coerce_to_boolean()
1119  * Coerce an argument of a construct that requires boolean input
1120  * (AND, OR, NOT, etc). Also check that input is not a set.
1121  *
1122  * Returns the possibly-transformed node tree.
1123  *
1124  * As with coerce_type, pstate may be NULL if no special unknown-Param
1125  * processing is wanted.
1126  */
1127 Node *
1129  const char *constructName)
1130 {
1131  Oid inputTypeId = exprType(node);
1132 
1133  if (inputTypeId != BOOLOID)
1134  {
1135  Node *newnode;
1136 
1137  newnode = coerce_to_target_type(pstate, node, inputTypeId,
1138  BOOLOID, -1,
1141  -1);
1142  if (newnode == NULL)
1143  ereport(ERROR,
1144  (errcode(ERRCODE_DATATYPE_MISMATCH),
1145  /* translator: first %s is name of a SQL construct, eg WHERE */
1146  errmsg("argument of %s must be type %s, not type %s",
1147  constructName, "boolean",
1148  format_type_be(inputTypeId)),
1149  parser_errposition(pstate, exprLocation(node))));
1150  node = newnode;
1151  }
1152 
1153  if (expression_returns_set(node))
1154  ereport(ERROR,
1155  (errcode(ERRCODE_DATATYPE_MISMATCH),
1156  /* translator: %s is name of a SQL construct, eg WHERE */
1157  errmsg("argument of %s must not return a set",
1158  constructName),
1159  parser_errposition(pstate, exprLocation(node))));
1160 
1161  return node;
1162 }
1163 
1164 /*
1165  * coerce_to_specific_type_typmod()
1166  * Coerce an argument of a construct that requires a specific data type,
1167  * with a specific typmod. Also check that input is not a set.
1168  *
1169  * Returns the possibly-transformed node tree.
1170  *
1171  * As with coerce_type, pstate may be NULL if no special unknown-Param
1172  * processing is wanted.
1173  */
1174 Node *
1176  Oid targetTypeId, int32 targetTypmod,
1177  const char *constructName)
1178 {
1179  Oid inputTypeId = exprType(node);
1180 
1181  if (inputTypeId != targetTypeId)
1182  {
1183  Node *newnode;
1184 
1185  newnode = coerce_to_target_type(pstate, node, inputTypeId,
1186  targetTypeId, targetTypmod,
1189  -1);
1190  if (newnode == NULL)
1191  ereport(ERROR,
1192  (errcode(ERRCODE_DATATYPE_MISMATCH),
1193  /* translator: first %s is name of a SQL construct, eg LIMIT */
1194  errmsg("argument of %s must be type %s, not type %s",
1195  constructName,
1196  format_type_be(targetTypeId),
1197  format_type_be(inputTypeId)),
1198  parser_errposition(pstate, exprLocation(node))));
1199  node = newnode;
1200  }
1201 
1202  if (expression_returns_set(node))
1203  ereport(ERROR,
1204  (errcode(ERRCODE_DATATYPE_MISMATCH),
1205  /* translator: %s is name of a SQL construct, eg LIMIT */
1206  errmsg("argument of %s must not return a set",
1207  constructName),
1208  parser_errposition(pstate, exprLocation(node))));
1209 
1210  return node;
1211 }
1212 
1213 /*
1214  * coerce_to_specific_type()
1215  * Coerce an argument of a construct that requires a specific data type.
1216  * Also check that input is not a set.
1217  *
1218  * Returns the possibly-transformed node tree.
1219  *
1220  * As with coerce_type, pstate may be NULL if no special unknown-Param
1221  * processing is wanted.
1222  */
1223 Node *
1225  Oid targetTypeId,
1226  const char *constructName)
1227 {
1228  return coerce_to_specific_type_typmod(pstate, node,
1229  targetTypeId, -1,
1230  constructName);
1231 }
1232 
1233 /*
1234  * parser_coercion_errposition - report coercion error location, if possible
1235  *
1236  * We prefer to point at the coercion request (CAST, ::, etc) if possible;
1237  * but there may be no such location in the case of an implicit coercion.
1238  * In that case point at the input expression.
1239  *
1240  * XXX possibly this is more generally useful than coercion errors;
1241  * if so, should rename and place with parser_errposition.
1242  */
1243 int
1245  int coerce_location,
1246  Node *input_expr)
1247 {
1248  if (coerce_location >= 0)
1249  return parser_errposition(pstate, coerce_location);
1250  else
1251  return parser_errposition(pstate, exprLocation(input_expr));
1252 }
1253 
1254 
1255 /*
1256  * select_common_type()
1257  * Determine the common supertype of a list of input expressions.
1258  * This is used for determining the output type of CASE, UNION,
1259  * and similar constructs.
1260  *
1261  * 'exprs' is a *nonempty* list of expressions. Note that earlier items
1262  * in the list will be preferred if there is doubt.
1263  * 'context' is a phrase to use in the error message if we fail to select
1264  * a usable type. Pass NULL to have the routine return InvalidOid
1265  * rather than throwing an error on failure.
1266  * 'which_expr': if not NULL, receives a pointer to the particular input
1267  * expression from which the result type was taken.
1268  */
1269 Oid
1270 select_common_type(ParseState *pstate, List *exprs, const char *context,
1271  Node **which_expr)
1272 {
1273  Node *pexpr;
1274  Oid ptype;
1275  TYPCATEGORY pcategory;
1276  bool pispreferred;
1277  ListCell *lc;
1278 
1279  Assert(exprs != NIL);
1280  pexpr = (Node *) linitial(exprs);
1281  lc = lnext(list_head(exprs));
1282  ptype = exprType(pexpr);
1283 
1284  /*
1285  * If all input types are valid and exactly the same, just pick that type.
1286  * This is the only way that we will resolve the result as being a domain
1287  * type; otherwise domains are smashed to their base types for comparison.
1288  */
1289  if (ptype != UNKNOWNOID)
1290  {
1291  for_each_cell(lc, lc)
1292  {
1293  Node *nexpr = (Node *) lfirst(lc);
1294  Oid ntype = exprType(nexpr);
1295 
1296  if (ntype != ptype)
1297  break;
1298  }
1299  if (lc == NULL) /* got to the end of the list? */
1300  {
1301  if (which_expr)
1302  *which_expr = pexpr;
1303  return ptype;
1304  }
1305  }
1306 
1307  /*
1308  * Nope, so set up for the full algorithm. Note that at this point, lc
1309  * points to the first list item with type different from pexpr's; we need
1310  * not re-examine any items the previous loop advanced over.
1311  */
1312  ptype = getBaseType(ptype);
1313  get_type_category_preferred(ptype, &pcategory, &pispreferred);
1314 
1315  for_each_cell(lc, lc)
1316  {
1317  Node *nexpr = (Node *) lfirst(lc);
1318  Oid ntype = getBaseType(exprType(nexpr));
1319 
1320  /* move on to next one if no new information... */
1321  if (ntype != UNKNOWNOID && ntype != ptype)
1322  {
1323  TYPCATEGORY ncategory;
1324  bool nispreferred;
1325 
1326  get_type_category_preferred(ntype, &ncategory, &nispreferred);
1327  if (ptype == UNKNOWNOID)
1328  {
1329  /* so far, only unknowns so take anything... */
1330  pexpr = nexpr;
1331  ptype = ntype;
1332  pcategory = ncategory;
1333  pispreferred = nispreferred;
1334  }
1335  else if (ncategory != pcategory)
1336  {
1337  /*
1338  * both types in different categories? then not much hope...
1339  */
1340  if (context == NULL)
1341  return InvalidOid;
1342  ereport(ERROR,
1343  (errcode(ERRCODE_DATATYPE_MISMATCH),
1344  /*------
1345  translator: first %s is name of a SQL construct, eg CASE */
1346  errmsg("%s types %s and %s cannot be matched",
1347  context,
1348  format_type_be(ptype),
1349  format_type_be(ntype)),
1350  parser_errposition(pstate, exprLocation(nexpr))));
1351  }
1352  else if (!pispreferred &&
1353  can_coerce_type(1, &ptype, &ntype, COERCION_IMPLICIT) &&
1354  !can_coerce_type(1, &ntype, &ptype, COERCION_IMPLICIT))
1355  {
1356  /*
1357  * take new type if can coerce to it implicitly but not the
1358  * other way; but if we have a preferred type, stay on it.
1359  */
1360  pexpr = nexpr;
1361  ptype = ntype;
1362  pcategory = ncategory;
1363  pispreferred = nispreferred;
1364  }
1365  }
1366  }
1367 
1368  /*
1369  * If all the inputs were UNKNOWN type --- ie, unknown-type literals ---
1370  * then resolve as type TEXT. This situation comes up with constructs
1371  * like SELECT (CASE WHEN foo THEN 'bar' ELSE 'baz' END); SELECT 'foo'
1372  * UNION SELECT 'bar'; It might seem desirable to leave the construct's
1373  * output type as UNKNOWN, but that really doesn't work, because we'd
1374  * probably end up needing a runtime coercion from UNKNOWN to something
1375  * else, and we usually won't have it. We need to coerce the unknown
1376  * literals while they are still literals, so a decision has to be made
1377  * now.
1378  */
1379  if (ptype == UNKNOWNOID)
1380  ptype = TEXTOID;
1381 
1382  if (which_expr)
1383  *which_expr = pexpr;
1384  return ptype;
1385 }
1386 
1387 /*
1388  * coerce_to_common_type()
1389  * Coerce an expression to the given type.
1390  *
1391  * This is used following select_common_type() to coerce the individual
1392  * expressions to the desired type. 'context' is a phrase to use in the
1393  * error message if we fail to coerce.
1394  *
1395  * As with coerce_type, pstate may be NULL if no special unknown-Param
1396  * processing is wanted.
1397  */
1398 Node *
1400  Oid targetTypeId, const char *context)
1401 {
1402  Oid inputTypeId = exprType(node);
1403 
1404  if (inputTypeId == targetTypeId)
1405  return node; /* no work */
1406  if (can_coerce_type(1, &inputTypeId, &targetTypeId, COERCION_IMPLICIT))
1407  node = coerce_type(pstate, node, inputTypeId, targetTypeId, -1,
1409  else
1410  ereport(ERROR,
1411  (errcode(ERRCODE_CANNOT_COERCE),
1412  /* translator: first %s is name of a SQL construct, eg CASE */
1413  errmsg("%s could not convert type %s to %s",
1414  context,
1415  format_type_be(inputTypeId),
1416  format_type_be(targetTypeId)),
1417  parser_errposition(pstate, exprLocation(node))));
1418  return node;
1419 }
1420 
1421 /*
1422  * check_generic_type_consistency()
1423  * Are the actual arguments potentially compatible with a
1424  * polymorphic function?
1425  *
1426  * The argument consistency rules are:
1427  *
1428  * 1) All arguments declared ANYELEMENT must have the same datatype.
1429  * 2) All arguments declared ANYARRAY must have the same datatype,
1430  * which must be a varlena array type.
1431  * 3) All arguments declared ANYRANGE must have the same datatype,
1432  * which must be a range type.
1433  * 4) If there are arguments of both ANYELEMENT and ANYARRAY, make sure the
1434  * actual ANYELEMENT datatype is in fact the element type for the actual
1435  * ANYARRAY datatype.
1436  * 5) Similarly, if there are arguments of both ANYELEMENT and ANYRANGE,
1437  * make sure the actual ANYELEMENT datatype is in fact the subtype for
1438  * the actual ANYRANGE type.
1439  * 6) ANYENUM is treated the same as ANYELEMENT except that if it is used
1440  * (alone or in combination with plain ANYELEMENT), we add the extra
1441  * condition that the ANYELEMENT type must be an enum.
1442  * 7) ANYNONARRAY is treated the same as ANYELEMENT except that if it is used,
1443  * we add the extra condition that the ANYELEMENT type must not be an array.
1444  * (This is a no-op if used in combination with ANYARRAY or ANYENUM, but
1445  * is an extra restriction if not.)
1446  *
1447  * Domains over arrays match ANYARRAY, and are immediately flattened to their
1448  * base type. (Thus, for example, we will consider it a match if one ANYARRAY
1449  * argument is a domain over int4[] while another one is just int4[].) Also
1450  * notice that such a domain does *not* match ANYNONARRAY.
1451  *
1452  * Similarly, domains over ranges match ANYRANGE, and are immediately
1453  * flattened to their base type.
1454  *
1455  * Note that domains aren't currently considered to match ANYENUM,
1456  * even if their base type would match.
1457  *
1458  * If we have UNKNOWN input (ie, an untyped literal) for any polymorphic
1459  * argument, assume it is okay.
1460  *
1461  * If an input is of type ANYARRAY (ie, we know it's an array, but not
1462  * what element type), we will accept it as a match to an argument declared
1463  * ANYARRAY, so long as we don't have to determine an element type ---
1464  * that is, so long as there is no use of ANYELEMENT. This is mostly for
1465  * backwards compatibility with the pre-7.4 behavior of ANYARRAY.
1466  *
1467  * We do not ereport here, but just return false if a rule is violated.
1468  */
1469 bool
1471  Oid *declared_arg_types,
1472  int nargs)
1473 {
1474  int j;
1475  Oid elem_typeid = InvalidOid;
1476  Oid array_typeid = InvalidOid;
1477  Oid array_typelem;
1478  Oid range_typeid = InvalidOid;
1479  Oid range_typelem;
1480  bool have_anyelement = false;
1481  bool have_anynonarray = false;
1482  bool have_anyenum = false;
1483 
1484  /*
1485  * Loop through the arguments to see if we have any that are polymorphic.
1486  * If so, require the actual types to be consistent.
1487  */
1488  for (j = 0; j < nargs; j++)
1489  {
1490  Oid decl_type = declared_arg_types[j];
1491  Oid actual_type = actual_arg_types[j];
1492 
1493  if (decl_type == ANYELEMENTOID ||
1494  decl_type == ANYNONARRAYOID ||
1495  decl_type == ANYENUMOID)
1496  {
1497  have_anyelement = true;
1498  if (decl_type == ANYNONARRAYOID)
1499  have_anynonarray = true;
1500  else if (decl_type == ANYENUMOID)
1501  have_anyenum = true;
1502  if (actual_type == UNKNOWNOID)
1503  continue;
1504  if (OidIsValid(elem_typeid) && actual_type != elem_typeid)
1505  return false;
1506  elem_typeid = actual_type;
1507  }
1508  else if (decl_type == ANYARRAYOID)
1509  {
1510  if (actual_type == UNKNOWNOID)
1511  continue;
1512  actual_type = getBaseType(actual_type); /* flatten domains */
1513  if (OidIsValid(array_typeid) && actual_type != array_typeid)
1514  return false;
1515  array_typeid = actual_type;
1516  }
1517  else if (decl_type == ANYRANGEOID)
1518  {
1519  if (actual_type == UNKNOWNOID)
1520  continue;
1521  actual_type = getBaseType(actual_type); /* flatten domains */
1522  if (OidIsValid(range_typeid) && actual_type != range_typeid)
1523  return false;
1524  range_typeid = actual_type;
1525  }
1526  }
1527 
1528  /* Get the element type based on the array type, if we have one */
1529  if (OidIsValid(array_typeid))
1530  {
1531  if (array_typeid == ANYARRAYOID)
1532  {
1533  /* Special case for ANYARRAY input: okay iff no ANYELEMENT */
1534  if (have_anyelement)
1535  return false;
1536  return true;
1537  }
1538 
1539  array_typelem = get_element_type(array_typeid);
1540  if (!OidIsValid(array_typelem))
1541  return false; /* should be an array, but isn't */
1542 
1543  if (!OidIsValid(elem_typeid))
1544  {
1545  /*
1546  * if we don't have an element type yet, use the one we just got
1547  */
1548  elem_typeid = array_typelem;
1549  }
1550  else if (array_typelem != elem_typeid)
1551  {
1552  /* otherwise, they better match */
1553  return false;
1554  }
1555  }
1556 
1557  /* Get the element type based on the range type, if we have one */
1558  if (OidIsValid(range_typeid))
1559  {
1560  range_typelem = get_range_subtype(range_typeid);
1561  if (!OidIsValid(range_typelem))
1562  return false; /* should be a range, but isn't */
1563 
1564  if (!OidIsValid(elem_typeid))
1565  {
1566  /*
1567  * if we don't have an element type yet, use the one we just got
1568  */
1569  elem_typeid = range_typelem;
1570  }
1571  else if (range_typelem != elem_typeid)
1572  {
1573  /* otherwise, they better match */
1574  return false;
1575  }
1576  }
1577 
1578  if (have_anynonarray)
1579  {
1580  /* require the element type to not be an array or domain over array */
1581  if (type_is_array_domain(elem_typeid))
1582  return false;
1583  }
1584 
1585  if (have_anyenum)
1586  {
1587  /* require the element type to be an enum */
1588  if (!type_is_enum(elem_typeid))
1589  return false;
1590  }
1591 
1592  /* Looks valid */
1593  return true;
1594 }
1595 
1596 /*
1597  * enforce_generic_type_consistency()
1598  * Make sure a polymorphic function is legally callable, and
1599  * deduce actual argument and result types.
1600  *
1601  * If any polymorphic pseudotype is used in a function's arguments or
1602  * return type, we make sure the actual data types are consistent with
1603  * each other. The argument consistency rules are shown above for
1604  * check_generic_type_consistency().
1605  *
1606  * If we have UNKNOWN input (ie, an untyped literal) for any polymorphic
1607  * argument, we attempt to deduce the actual type it should have. If
1608  * successful, we alter that position of declared_arg_types[] so that
1609  * make_fn_arguments will coerce the literal to the right thing.
1610  *
1611  * Rules are applied to the function's return type (possibly altering it)
1612  * if it is declared as a polymorphic type:
1613  *
1614  * 1) If return type is ANYARRAY, and any argument is ANYARRAY, use the
1615  * argument's actual type as the function's return type.
1616  * 2) Similarly, if return type is ANYRANGE, and any argument is ANYRANGE,
1617  * use the argument's actual type as the function's return type.
1618  * 3) If return type is ANYARRAY, no argument is ANYARRAY, but any argument is
1619  * ANYELEMENT, use the actual type of the argument to determine the
1620  * function's return type, i.e. the element type's corresponding array
1621  * type. (Note: similar behavior does not exist for ANYRANGE, because it's
1622  * impossible to determine the range type from the subtype alone.)
1623  * 4) If return type is ANYARRAY, but no argument is ANYARRAY or ANYELEMENT,
1624  * generate an error. Similarly, if return type is ANYRANGE, but no
1625  * argument is ANYRANGE, generate an error. (These conditions are
1626  * prevented by CREATE FUNCTION and therefore are not expected here.)
1627  * 5) If return type is ANYELEMENT, and any argument is ANYELEMENT, use the
1628  * argument's actual type as the function's return type.
1629  * 6) If return type is ANYELEMENT, no argument is ANYELEMENT, but any argument
1630  * is ANYARRAY or ANYRANGE, use the actual type of the argument to determine
1631  * the function's return type, i.e. the array type's corresponding element
1632  * type or the range type's corresponding subtype (or both, in which case
1633  * they must match).
1634  * 7) If return type is ANYELEMENT, no argument is ANYELEMENT, ANYARRAY, or
1635  * ANYRANGE, generate an error. (This condition is prevented by CREATE
1636  * FUNCTION and therefore is not expected here.)
1637  * 8) ANYENUM is treated the same as ANYELEMENT except that if it is used
1638  * (alone or in combination with plain ANYELEMENT), we add the extra
1639  * condition that the ANYELEMENT type must be an enum.
1640  * 9) ANYNONARRAY is treated the same as ANYELEMENT except that if it is used,
1641  * we add the extra condition that the ANYELEMENT type must not be an array.
1642  * (This is a no-op if used in combination with ANYARRAY or ANYENUM, but
1643  * is an extra restriction if not.)
1644  *
1645  * Domains over arrays or ranges match ANYARRAY or ANYRANGE arguments,
1646  * respectively, and are immediately flattened to their base type. (In
1647  * particular, if the return type is also ANYARRAY or ANYRANGE, we'll set it
1648  * to the base type not the domain type.)
1649  *
1650  * When allow_poly is false, we are not expecting any of the actual_arg_types
1651  * to be polymorphic, and we should not return a polymorphic result type
1652  * either. When allow_poly is true, it is okay to have polymorphic "actual"
1653  * arg types, and we can return ANYARRAY, ANYRANGE, or ANYELEMENT as the
1654  * result. (This case is currently used only to check compatibility of an
1655  * aggregate's declaration with the underlying transfn.)
1656  *
1657  * A special case is that we could see ANYARRAY as an actual_arg_type even
1658  * when allow_poly is false (this is possible only because pg_statistic has
1659  * columns shown as anyarray in the catalogs). We allow this to match a
1660  * declared ANYARRAY argument, but only if there is no ANYELEMENT argument
1661  * or result (since we can't determine a specific element type to match to
1662  * ANYELEMENT). Note this means that functions taking ANYARRAY had better
1663  * behave sanely if applied to the pg_statistic columns; they can't just
1664  * assume that successive inputs are of the same actual element type.
1665  */
1666 Oid
1668  Oid *declared_arg_types,
1669  int nargs,
1670  Oid rettype,
1671  bool allow_poly)
1672 {
1673  int j;
1674  bool have_generics = false;
1675  bool have_unknowns = false;
1676  Oid elem_typeid = InvalidOid;
1677  Oid array_typeid = InvalidOid;
1678  Oid range_typeid = InvalidOid;
1679  Oid array_typelem;
1680  Oid range_typelem;
1681  bool have_anyelement = (rettype == ANYELEMENTOID ||
1682  rettype == ANYNONARRAYOID ||
1683  rettype == ANYENUMOID);
1684  bool have_anynonarray = (rettype == ANYNONARRAYOID);
1685  bool have_anyenum = (rettype == ANYENUMOID);
1686 
1687  /*
1688  * Loop through the arguments to see if we have any that are polymorphic.
1689  * If so, require the actual types to be consistent.
1690  */
1691  for (j = 0; j < nargs; j++)
1692  {
1693  Oid decl_type = declared_arg_types[j];
1694  Oid actual_type = actual_arg_types[j];
1695 
1696  if (decl_type == ANYELEMENTOID ||
1697  decl_type == ANYNONARRAYOID ||
1698  decl_type == ANYENUMOID)
1699  {
1700  have_generics = have_anyelement = true;
1701  if (decl_type == ANYNONARRAYOID)
1702  have_anynonarray = true;
1703  else if (decl_type == ANYENUMOID)
1704  have_anyenum = true;
1705  if (actual_type == UNKNOWNOID)
1706  {
1707  have_unknowns = true;
1708  continue;
1709  }
1710  if (allow_poly && decl_type == actual_type)
1711  continue; /* no new information here */
1712  if (OidIsValid(elem_typeid) && actual_type != elem_typeid)
1713  ereport(ERROR,
1714  (errcode(ERRCODE_DATATYPE_MISMATCH),
1715  errmsg("arguments declared \"anyelement\" are not all alike"),
1716  errdetail("%s versus %s",
1717  format_type_be(elem_typeid),
1718  format_type_be(actual_type))));
1719  elem_typeid = actual_type;
1720  }
1721  else if (decl_type == ANYARRAYOID)
1722  {
1723  have_generics = true;
1724  if (actual_type == UNKNOWNOID)
1725  {
1726  have_unknowns = true;
1727  continue;
1728  }
1729  if (allow_poly && decl_type == actual_type)
1730  continue; /* no new information here */
1731  actual_type = getBaseType(actual_type); /* flatten domains */
1732  if (OidIsValid(array_typeid) && actual_type != array_typeid)
1733  ereport(ERROR,
1734  (errcode(ERRCODE_DATATYPE_MISMATCH),
1735  errmsg("arguments declared \"anyarray\" are not all alike"),
1736  errdetail("%s versus %s",
1737  format_type_be(array_typeid),
1738  format_type_be(actual_type))));
1739  array_typeid = actual_type;
1740  }
1741  else if (decl_type == ANYRANGEOID)
1742  {
1743  have_generics = true;
1744  if (actual_type == UNKNOWNOID)
1745  {
1746  have_unknowns = true;
1747  continue;
1748  }
1749  if (allow_poly && decl_type == actual_type)
1750  continue; /* no new information here */
1751  actual_type = getBaseType(actual_type); /* flatten domains */
1752  if (OidIsValid(range_typeid) && actual_type != range_typeid)
1753  ereport(ERROR,
1754  (errcode(ERRCODE_DATATYPE_MISMATCH),
1755  errmsg("arguments declared \"anyrange\" are not all alike"),
1756  errdetail("%s versus %s",
1757  format_type_be(range_typeid),
1758  format_type_be(actual_type))));
1759  range_typeid = actual_type;
1760  }
1761  }
1762 
1763  /*
1764  * Fast Track: if none of the arguments are polymorphic, return the
1765  * unmodified rettype. We assume it can't be polymorphic either.
1766  */
1767  if (!have_generics)
1768  return rettype;
1769 
1770  /* Get the element type based on the array type, if we have one */
1771  if (OidIsValid(array_typeid))
1772  {
1773  if (array_typeid == ANYARRAYOID && !have_anyelement)
1774  {
1775  /* Special case for ANYARRAY input: okay iff no ANYELEMENT */
1776  array_typelem = ANYELEMENTOID;
1777  }
1778  else
1779  {
1780  array_typelem = get_element_type(array_typeid);
1781  if (!OidIsValid(array_typelem))
1782  ereport(ERROR,
1783  (errcode(ERRCODE_DATATYPE_MISMATCH),
1784  errmsg("argument declared %s is not an array but type %s",
1785  "anyarray", format_type_be(array_typeid))));
1786  }
1787 
1788  if (!OidIsValid(elem_typeid))
1789  {
1790  /*
1791  * if we don't have an element type yet, use the one we just got
1792  */
1793  elem_typeid = array_typelem;
1794  }
1795  else if (array_typelem != elem_typeid)
1796  {
1797  /* otherwise, they better match */
1798  ereport(ERROR,
1799  (errcode(ERRCODE_DATATYPE_MISMATCH),
1800  errmsg("argument declared %s is not consistent with argument declared %s",
1801  "anyarray", "anyelement"),
1802  errdetail("%s versus %s",
1803  format_type_be(array_typeid),
1804  format_type_be(elem_typeid))));
1805  }
1806  }
1807 
1808  /* Get the element type based on the range type, if we have one */
1809  if (OidIsValid(range_typeid))
1810  {
1811  if (range_typeid == ANYRANGEOID && !have_anyelement)
1812  {
1813  /* Special case for ANYRANGE input: okay iff no ANYELEMENT */
1814  range_typelem = ANYELEMENTOID;
1815  }
1816  else
1817  {
1818  range_typelem = get_range_subtype(range_typeid);
1819  if (!OidIsValid(range_typelem))
1820  ereport(ERROR,
1821  (errcode(ERRCODE_DATATYPE_MISMATCH),
1822  errmsg("argument declared %s is not a range type but type %s",
1823  "anyrange",
1824  format_type_be(range_typeid))));
1825  }
1826 
1827  if (!OidIsValid(elem_typeid))
1828  {
1829  /*
1830  * if we don't have an element type yet, use the one we just got
1831  */
1832  elem_typeid = range_typelem;
1833  }
1834  else if (range_typelem != elem_typeid)
1835  {
1836  /* otherwise, they better match */
1837  ereport(ERROR,
1838  (errcode(ERRCODE_DATATYPE_MISMATCH),
1839  errmsg("argument declared %s is not consistent with argument declared %s",
1840  "anyrange", "anyelement"),
1841  errdetail("%s versus %s",
1842  format_type_be(range_typeid),
1843  format_type_be(elem_typeid))));
1844  }
1845  }
1846 
1847  if (!OidIsValid(elem_typeid))
1848  {
1849  if (allow_poly)
1850  {
1851  elem_typeid = ANYELEMENTOID;
1852  array_typeid = ANYARRAYOID;
1853  range_typeid = ANYRANGEOID;
1854  }
1855  else
1856  {
1857  /* Only way to get here is if all the generic args are UNKNOWN */
1858  ereport(ERROR,
1859  (errcode(ERRCODE_DATATYPE_MISMATCH),
1860  errmsg("could not determine polymorphic type because input has type %s",
1861  "unknown")));
1862  }
1863  }
1864 
1865  if (have_anynonarray && elem_typeid != ANYELEMENTOID)
1866  {
1867  /* require the element type to not be an array or domain over array */
1868  if (type_is_array_domain(elem_typeid))
1869  ereport(ERROR,
1870  (errcode(ERRCODE_DATATYPE_MISMATCH),
1871  errmsg("type matched to anynonarray is an array type: %s",
1872  format_type_be(elem_typeid))));
1873  }
1874 
1875  if (have_anyenum && elem_typeid != ANYELEMENTOID)
1876  {
1877  /* require the element type to be an enum */
1878  if (!type_is_enum(elem_typeid))
1879  ereport(ERROR,
1880  (errcode(ERRCODE_DATATYPE_MISMATCH),
1881  errmsg("type matched to anyenum is not an enum type: %s",
1882  format_type_be(elem_typeid))));
1883  }
1884 
1885  /*
1886  * If we had any unknown inputs, re-scan to assign correct types
1887  */
1888  if (have_unknowns)
1889  {
1890  for (j = 0; j < nargs; j++)
1891  {
1892  Oid decl_type = declared_arg_types[j];
1893  Oid actual_type = actual_arg_types[j];
1894 
1895  if (actual_type != UNKNOWNOID)
1896  continue;
1897 
1898  if (decl_type == ANYELEMENTOID ||
1899  decl_type == ANYNONARRAYOID ||
1900  decl_type == ANYENUMOID)
1901  declared_arg_types[j] = elem_typeid;
1902  else if (decl_type == ANYARRAYOID)
1903  {
1904  if (!OidIsValid(array_typeid))
1905  {
1906  array_typeid = get_array_type(elem_typeid);
1907  if (!OidIsValid(array_typeid))
1908  ereport(ERROR,
1909  (errcode(ERRCODE_UNDEFINED_OBJECT),
1910  errmsg("could not find array type for data type %s",
1911  format_type_be(elem_typeid))));
1912  }
1913  declared_arg_types[j] = array_typeid;
1914  }
1915  else if (decl_type == ANYRANGEOID)
1916  {
1917  if (!OidIsValid(range_typeid))
1918  {
1919  ereport(ERROR,
1920  (errcode(ERRCODE_UNDEFINED_OBJECT),
1921  errmsg("could not find range type for data type %s",
1922  format_type_be(elem_typeid))));
1923  }
1924  declared_arg_types[j] = range_typeid;
1925  }
1926  }
1927  }
1928 
1929  /* if we return ANYARRAY use the appropriate argument type */
1930  if (rettype == ANYARRAYOID)
1931  {
1932  if (!OidIsValid(array_typeid))
1933  {
1934  array_typeid = get_array_type(elem_typeid);
1935  if (!OidIsValid(array_typeid))
1936  ereport(ERROR,
1937  (errcode(ERRCODE_UNDEFINED_OBJECT),
1938  errmsg("could not find array type for data type %s",
1939  format_type_be(elem_typeid))));
1940  }
1941  return array_typeid;
1942  }
1943 
1944  /* if we return ANYRANGE use the appropriate argument type */
1945  if (rettype == ANYRANGEOID)
1946  {
1947  if (!OidIsValid(range_typeid))
1948  {
1949  ereport(ERROR,
1950  (errcode(ERRCODE_UNDEFINED_OBJECT),
1951  errmsg("could not find range type for data type %s",
1952  format_type_be(elem_typeid))));
1953  }
1954  return range_typeid;
1955  }
1956 
1957  /* if we return ANYELEMENT use the appropriate argument type */
1958  if (rettype == ANYELEMENTOID ||
1959  rettype == ANYNONARRAYOID ||
1960  rettype == ANYENUMOID)
1961  return elem_typeid;
1962 
1963  /* we don't return a generic type; send back the original return type */
1964  return rettype;
1965 }
1966 
1967 /*
1968  * resolve_generic_type()
1969  * Deduce an individual actual datatype on the assumption that
1970  * the rules for polymorphic types are being followed.
1971  *
1972  * declared_type is the declared datatype we want to resolve.
1973  * context_actual_type is the actual input datatype to some argument
1974  * that has declared datatype context_declared_type.
1975  *
1976  * If declared_type isn't polymorphic, we just return it. Otherwise,
1977  * context_declared_type must be polymorphic, and we deduce the correct
1978  * return type based on the relationship of the two polymorphic types.
1979  */
1980 Oid
1982  Oid context_actual_type,
1983  Oid context_declared_type)
1984 {
1985  if (declared_type == ANYARRAYOID)
1986  {
1987  if (context_declared_type == ANYARRAYOID)
1988  {
1989  /*
1990  * Use actual type, but it must be an array; or if it's a domain
1991  * over array, use the base array type.
1992  */
1993  Oid context_base_type = getBaseType(context_actual_type);
1994  Oid array_typelem = get_element_type(context_base_type);
1995 
1996  if (!OidIsValid(array_typelem))
1997  ereport(ERROR,
1998  (errcode(ERRCODE_DATATYPE_MISMATCH),
1999  errmsg("argument declared %s is not an array but type %s",
2000  "anyarray", format_type_be(context_base_type))));
2001  return context_base_type;
2002  }
2003  else if (context_declared_type == ANYELEMENTOID ||
2004  context_declared_type == ANYNONARRAYOID ||
2005  context_declared_type == ANYENUMOID ||
2006  context_declared_type == ANYRANGEOID)
2007  {
2008  /* Use the array type corresponding to actual type */
2009  Oid array_typeid = get_array_type(context_actual_type);
2010 
2011  if (!OidIsValid(array_typeid))
2012  ereport(ERROR,
2013  (errcode(ERRCODE_UNDEFINED_OBJECT),
2014  errmsg("could not find array type for data type %s",
2015  format_type_be(context_actual_type))));
2016  return array_typeid;
2017  }
2018  }
2019  else if (declared_type == ANYELEMENTOID ||
2020  declared_type == ANYNONARRAYOID ||
2021  declared_type == ANYENUMOID ||
2022  declared_type == ANYRANGEOID)
2023  {
2024  if (context_declared_type == ANYARRAYOID)
2025  {
2026  /* Use the element type corresponding to actual type */
2027  Oid context_base_type = getBaseType(context_actual_type);
2028  Oid array_typelem = get_element_type(context_base_type);
2029 
2030  if (!OidIsValid(array_typelem))
2031  ereport(ERROR,
2032  (errcode(ERRCODE_DATATYPE_MISMATCH),
2033  errmsg("argument declared %s is not an array but type %s",
2034  "anyarray", format_type_be(context_base_type))));
2035  return array_typelem;
2036  }
2037  else if (context_declared_type == ANYRANGEOID)
2038  {
2039  /* Use the element type corresponding to actual type */
2040  Oid context_base_type = getBaseType(context_actual_type);
2041  Oid range_typelem = get_range_subtype(context_base_type);
2042 
2043  if (!OidIsValid(range_typelem))
2044  ereport(ERROR,
2045  (errcode(ERRCODE_DATATYPE_MISMATCH),
2046  errmsg("argument declared %s is not a range type but type %s",
2047  "anyrange", format_type_be(context_base_type))));
2048  return range_typelem;
2049  }
2050  else if (context_declared_type == ANYELEMENTOID ||
2051  context_declared_type == ANYNONARRAYOID ||
2052  context_declared_type == ANYENUMOID)
2053  {
2054  /* Use the actual type; it doesn't matter if array or not */
2055  return context_actual_type;
2056  }
2057  }
2058  else
2059  {
2060  /* declared_type isn't polymorphic, so return it as-is */
2061  return declared_type;
2062  }
2063  /* If we get here, declared_type is polymorphic and context isn't */
2064  /* NB: this is a calling-code logic error, not a user error */
2065  elog(ERROR, "could not determine polymorphic type because context isn't polymorphic");
2066  return InvalidOid; /* keep compiler quiet */
2067 }
2068 
2069 
2070 /* TypeCategory()
2071  * Assign a category to the specified type OID.
2072  *
2073  * NB: this must not return TYPCATEGORY_INVALID.
2074  */
2077 {
2078  char typcategory;
2079  bool typispreferred;
2080 
2081  get_type_category_preferred(type, &typcategory, &typispreferred);
2082  Assert(typcategory != TYPCATEGORY_INVALID);
2083  return (TYPCATEGORY) typcategory;
2084 }
2085 
2086 
2087 /* IsPreferredType()
2088  * Check if this type is a preferred type for the given category.
2089  *
2090  * If category is TYPCATEGORY_INVALID, then we'll return true for preferred
2091  * types of any category; otherwise, only for preferred types of that
2092  * category.
2093  */
2094 bool
2096 {
2097  char typcategory;
2098  bool typispreferred;
2099 
2100  get_type_category_preferred(type, &typcategory, &typispreferred);
2101  if (category == typcategory || category == TYPCATEGORY_INVALID)
2102  return typispreferred;
2103  else
2104  return false;
2105 }
2106 
2107 
2108 /* IsBinaryCoercible()
2109  * Check if srctype is binary-coercible to targettype.
2110  *
2111  * This notion allows us to cheat and directly exchange values without
2112  * going through the trouble of calling a conversion function. Note that
2113  * in general, this should only be an implementation shortcut. Before 7.4,
2114  * this was also used as a heuristic for resolving overloaded functions and
2115  * operators, but that's basically a bad idea.
2116  *
2117  * As of 7.3, binary coercibility isn't hardwired into the code anymore.
2118  * We consider two types binary-coercible if there is an implicitly
2119  * invokable, no-function-needed pg_cast entry. Also, a domain is always
2120  * binary-coercible to its base type, though *not* vice versa (in the other
2121  * direction, one must apply domain constraint checks before accepting the
2122  * value as legitimate). We also need to special-case various polymorphic
2123  * types.
2124  *
2125  * This function replaces IsBinaryCompatible(), which was an inherently
2126  * symmetric test. Since the pg_cast entries aren't necessarily symmetric,
2127  * the order of the operands is now significant.
2128  */
2129 bool
2130 IsBinaryCoercible(Oid srctype, Oid targettype)
2131 {
2132  HeapTuple tuple;
2133  Form_pg_cast castForm;
2134  bool result;
2135 
2136  /* Fast path if same type */
2137  if (srctype == targettype)
2138  return true;
2139 
2140  /* Anything is coercible to ANY or ANYELEMENT */
2141  if (targettype == ANYOID || targettype == ANYELEMENTOID)
2142  return true;
2143 
2144  /* If srctype is a domain, reduce to its base type */
2145  if (OidIsValid(srctype))
2146  srctype = getBaseType(srctype);
2147 
2148  /* Somewhat-fast path for domain -> base type case */
2149  if (srctype == targettype)
2150  return true;
2151 
2152  /* Also accept any array type as coercible to ANYARRAY */
2153  if (targettype == ANYARRAYOID)
2154  if (type_is_array(srctype))
2155  return true;
2156 
2157  /* Also accept any non-array type as coercible to ANYNONARRAY */
2158  if (targettype == ANYNONARRAYOID)
2159  if (!type_is_array(srctype))
2160  return true;
2161 
2162  /* Also accept any enum type as coercible to ANYENUM */
2163  if (targettype == ANYENUMOID)
2164  if (type_is_enum(srctype))
2165  return true;
2166 
2167  /* Also accept any range type as coercible to ANYRANGE */
2168  if (targettype == ANYRANGEOID)
2169  if (type_is_range(srctype))
2170  return true;
2171 
2172  /* Also accept any composite type as coercible to RECORD */
2173  if (targettype == RECORDOID)
2174  if (ISCOMPLEX(srctype))
2175  return true;
2176 
2177  /* Also accept any composite array type as coercible to RECORD[] */
2178  if (targettype == RECORDARRAYOID)
2179  if (is_complex_array(srctype))
2180  return true;
2181 
2182  /* Else look in pg_cast */
2184  ObjectIdGetDatum(srctype),
2185  ObjectIdGetDatum(targettype));
2186  if (!HeapTupleIsValid(tuple))
2187  return false; /* no cast */
2188  castForm = (Form_pg_cast) GETSTRUCT(tuple);
2189 
2190  result = (castForm->castmethod == COERCION_METHOD_BINARY &&
2191  castForm->castcontext == COERCION_CODE_IMPLICIT);
2192 
2193  ReleaseSysCache(tuple);
2194 
2195  return result;
2196 }
2197 
2198 
2199 /*
2200  * find_coercion_pathway
2201  * Look for a coercion pathway between two types.
2202  *
2203  * Currently, this deals only with scalar-type cases; it does not consider
2204  * polymorphic types nor casts between composite types. (Perhaps fold
2205  * those in someday?)
2206  *
2207  * ccontext determines the set of available casts.
2208  *
2209  * The possible result codes are:
2210  * COERCION_PATH_NONE: failed to find any coercion pathway
2211  * *funcid is set to InvalidOid
2212  * COERCION_PATH_FUNC: apply the coercion function returned in *funcid
2213  * COERCION_PATH_RELABELTYPE: binary-compatible cast, no function needed
2214  * *funcid is set to InvalidOid
2215  * COERCION_PATH_ARRAYCOERCE: need an ArrayCoerceExpr node
2216  * *funcid is set to InvalidOid
2217  * COERCION_PATH_COERCEVIAIO: need a CoerceViaIO node
2218  * *funcid is set to InvalidOid
2219  *
2220  * Note: COERCION_PATH_RELABELTYPE does not necessarily mean that no work is
2221  * needed to do the coercion; if the target is a domain then we may need to
2222  * apply domain constraint checking. If you want to check for a zero-effort
2223  * conversion then use IsBinaryCoercible().
2224  */
2226 find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId,
2227  CoercionContext ccontext,
2228  Oid *funcid)
2229 {
2231  HeapTuple tuple;
2232 
2233  *funcid = InvalidOid;
2234 
2235  /* Perhaps the types are domains; if so, look at their base types */
2236  if (OidIsValid(sourceTypeId))
2237  sourceTypeId = getBaseType(sourceTypeId);
2238  if (OidIsValid(targetTypeId))
2239  targetTypeId = getBaseType(targetTypeId);
2240 
2241  /* Domains are always coercible to and from their base type */
2242  if (sourceTypeId == targetTypeId)
2244 
2245  /* Look in pg_cast */
2247  ObjectIdGetDatum(sourceTypeId),
2248  ObjectIdGetDatum(targetTypeId));
2249 
2250  if (HeapTupleIsValid(tuple))
2251  {
2252  Form_pg_cast castForm = (Form_pg_cast) GETSTRUCT(tuple);
2253  CoercionContext castcontext;
2254 
2255  /* convert char value for castcontext to CoercionContext enum */
2256  switch (castForm->castcontext)
2257  {
2258  case COERCION_CODE_IMPLICIT:
2259  castcontext = COERCION_IMPLICIT;
2260  break;
2261  case COERCION_CODE_ASSIGNMENT:
2262  castcontext = COERCION_ASSIGNMENT;
2263  break;
2264  case COERCION_CODE_EXPLICIT:
2265  castcontext = COERCION_EXPLICIT;
2266  break;
2267  default:
2268  elog(ERROR, "unrecognized castcontext: %d",
2269  (int) castForm->castcontext);
2270  castcontext = 0; /* keep compiler quiet */
2271  break;
2272  }
2273 
2274  /* Rely on ordering of enum for correct behavior here */
2275  if (ccontext >= castcontext)
2276  {
2277  switch (castForm->castmethod)
2278  {
2279  case COERCION_METHOD_FUNCTION:
2280  result = COERCION_PATH_FUNC;
2281  *funcid = castForm->castfunc;
2282  break;
2283  case COERCION_METHOD_INOUT:
2284  result = COERCION_PATH_COERCEVIAIO;
2285  break;
2286  case COERCION_METHOD_BINARY:
2287  result = COERCION_PATH_RELABELTYPE;
2288  break;
2289  default:
2290  elog(ERROR, "unrecognized castmethod: %d",
2291  (int) castForm->castmethod);
2292  break;
2293  }
2294  }
2295 
2296  ReleaseSysCache(tuple);
2297  }
2298  else
2299  {
2300  /*
2301  * If there's no pg_cast entry, perhaps we are dealing with a pair of
2302  * array types. If so, and if their element types have a conversion
2303  * pathway, report that we can coerce with an ArrayCoerceExpr.
2304  *
2305  * Hack: disallow coercions to oidvector and int2vector, which
2306  * otherwise tend to capture coercions that should go to "real" array
2307  * types. We want those types to be considered "real" arrays for many
2308  * purposes, but not this one. (Also, ArrayCoerceExpr isn't
2309  * guaranteed to produce an output that meets the restrictions of
2310  * these datatypes, such as being 1-dimensional.)
2311  */
2312  if (targetTypeId != OIDVECTOROID && targetTypeId != INT2VECTOROID)
2313  {
2314  Oid targetElem;
2315  Oid sourceElem;
2316 
2317  if ((targetElem = get_element_type(targetTypeId)) != InvalidOid &&
2318  (sourceElem = get_element_type(sourceTypeId)) != InvalidOid)
2319  {
2320  CoercionPathType elempathtype;
2321  Oid elemfuncid;
2322 
2323  elempathtype = find_coercion_pathway(targetElem,
2324  sourceElem,
2325  ccontext,
2326  &elemfuncid);
2327  if (elempathtype != COERCION_PATH_NONE)
2328  {
2329  result = COERCION_PATH_ARRAYCOERCE;
2330  }
2331  }
2332  }
2333 
2334  /*
2335  * If we still haven't found a possibility, consider automatic casting
2336  * using I/O functions. We allow assignment casts to string types and
2337  * explicit casts from string types to be handled this way. (The
2338  * CoerceViaIO mechanism is a lot more general than that, but this is
2339  * all we want to allow in the absence of a pg_cast entry.) It would
2340  * probably be better to insist on explicit casts in both directions,
2341  * but this is a compromise to preserve something of the pre-8.3
2342  * behavior that many types had implicit (yipes!) casts to text.
2343  */
2344  if (result == COERCION_PATH_NONE)
2345  {
2346  if (ccontext >= COERCION_ASSIGNMENT &&
2347  TypeCategory(targetTypeId) == TYPCATEGORY_STRING)
2348  result = COERCION_PATH_COERCEVIAIO;
2349  else if (ccontext >= COERCION_EXPLICIT &&
2350  TypeCategory(sourceTypeId) == TYPCATEGORY_STRING)
2351  result = COERCION_PATH_COERCEVIAIO;
2352  }
2353  }
2354 
2355  return result;
2356 }
2357 
2358 
2359 /*
2360  * find_typmod_coercion_function -- does the given type need length coercion?
2361  *
2362  * If the target type possesses a pg_cast function from itself to itself,
2363  * it must need length coercion.
2364  *
2365  * "bpchar" (ie, char(N)) and "numeric" are examples of such types.
2366  *
2367  * If the given type is a varlena array type, we do not look for a coercion
2368  * function associated directly with the array type, but instead look for
2369  * one associated with the element type. An ArrayCoerceExpr node must be
2370  * used to apply such a function. (Note: currently, it's pointless to
2371  * return the funcid in this case, because it'll just get looked up again
2372  * in the recursive construction of the ArrayCoerceExpr's elemexpr.)
2373  *
2374  * We use the same result enum as find_coercion_pathway, but the only possible
2375  * result codes are:
2376  * COERCION_PATH_NONE: no length coercion needed
2377  * COERCION_PATH_FUNC: apply the function returned in *funcid
2378  * COERCION_PATH_ARRAYCOERCE: apply the function using ArrayCoerceExpr
2379  */
2382  Oid *funcid)
2383 {
2384  CoercionPathType result;
2385  Type targetType;
2386  Form_pg_type typeForm;
2387  HeapTuple tuple;
2388 
2389  *funcid = InvalidOid;
2390  result = COERCION_PATH_FUNC;
2391 
2392  targetType = typeidType(typeId);
2393  typeForm = (Form_pg_type) GETSTRUCT(targetType);
2394 
2395  /* Check for a varlena array type */
2396  if (typeForm->typelem != InvalidOid && typeForm->typlen == -1)
2397  {
2398  /* Yes, switch our attention to the element type */
2399  typeId = typeForm->typelem;
2400  result = COERCION_PATH_ARRAYCOERCE;
2401  }
2402  ReleaseSysCache(targetType);
2403 
2404  /* Look in pg_cast */
2406  ObjectIdGetDatum(typeId),
2407  ObjectIdGetDatum(typeId));
2408 
2409  if (HeapTupleIsValid(tuple))
2410  {
2411  Form_pg_cast castForm = (Form_pg_cast) GETSTRUCT(tuple);
2412 
2413  *funcid = castForm->castfunc;
2414  ReleaseSysCache(tuple);
2415  }
2416 
2417  if (!OidIsValid(*funcid))
2418  result = COERCION_PATH_NONE;
2419 
2420  return result;
2421 }
2422 
2423 /*
2424  * is_complex_array
2425  * Is this type an array of composite?
2426  *
2427  * Note: this will not return true for record[]; check for RECORDARRAYOID
2428  * separately if needed.
2429  */
2430 static bool
2432 {
2433  Oid elemtype = get_element_type(typid);
2434 
2435  return (OidIsValid(elemtype) && ISCOMPLEX(elemtype));
2436 }
2437 
2438 
2439 /*
2440  * Check whether reltypeId is the row type of a typed table of type
2441  * reloftypeId, or is a domain over such a row type. (This is conceptually
2442  * similar to the subtype relationship checked by typeInheritsFrom().)
2443  */
2444 static bool
2445 typeIsOfTypedTable(Oid reltypeId, Oid reloftypeId)
2446 {
2447  Oid relid = typeOrDomainTypeRelid(reltypeId);
2448  bool result = false;
2449 
2450  if (relid)
2451  {
2452  HeapTuple tp;
2453  Form_pg_class reltup;
2454 
2455  tp = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
2456  if (!HeapTupleIsValid(tp))
2457  elog(ERROR, "cache lookup failed for relation %u", relid);
2458 
2459  reltup = (Form_pg_class) GETSTRUCT(tp);
2460  if (reltup->reloftype == reloftypeId)
2461  result = true;
2462 
2463  ReleaseSysCache(tp);
2464  }
2465 
2466  return result;
2467 }
Datum constvalue
Definition: primnodes.h:197
char typcategory
Definition: pg_type.h:84
#define NIL
Definition: pg_list.h:69
Oid getBaseTypeAndTypmod(Oid typid, int32 *typmod)
Definition: lsyscache.c:2292
List * args
Definition: primnodes.h:991
Oid typeTypeCollation(Type typ)
Definition: parse_type.c:621
#define IsA(nodeptr, _type_)
Definition: nodes.h:568
#define type_is_array_domain(typid)
Definition: lsyscache.h:182
#define GETSTRUCT(TUP)
Definition: htup_details.h:673
Oid typeOrDomainTypeRelid(Oid type_id)
Definition: parse_type.c:670
Oid resolve_generic_type(Oid declared_type, Oid context_actual_type, Oid context_declared_type)
bool constbyval
Definition: primnodes.h:200
int exprLocation(const Node *expr)
Definition: nodeFuncs.c:1186
TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod)
Definition: typcache.c:1641
int32 resulttypmod
Definition: primnodes.h:1230
int32 exprTypmod(const Node *expr)
Definition: nodeFuncs.c:276
int16 typeLen(Type t)
Definition: parse_type.c:580
Oid get_element_type(Oid typid)
Definition: lsyscache.c:2502
#define PointerGetDatum(X)
Definition: postgres.h:539
#define TupleDescAttr(tupdesc, i)
Definition: tupdesc.h:93
Oid get_array_type(Oid typid)
Definition: lsyscache.c:2530
Oid resulttype
Definition: primnodes.h:816
bool expression_returns_set(Node *clause)
Definition: nodeFuncs.c:670
bool datumIsEqual(Datum value1, Datum value2, bool typByVal, int typLen)
Definition: datum.c:219
CoerceParamHook p_coerce_param_hook
Definition: parse_node.h:215
Node * coerce_type(ParseState *pstate, Node *node, Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod, CoercionContext ccontext, CoercionForm cformat, int location)
Definition: parse_coerce.c:156
Definition: nodes.h:517
CoercionForm coercionformat
Definition: primnodes.h:1232
int errcode(int sqlerrcode)
Definition: elog.c:575
char * format_type_be(Oid type_oid)
Definition: format_type.c:328
bool type_is_range(Oid typid)
Definition: lsyscache.c:2442
unsigned int Oid
Definition: postgres_ext.h:31
Definition: primnodes.h:164
Const * makeConst(Oid consttype, int32 consttypmod, Oid constcollid, int constlen, Datum constvalue, bool constisnull, bool constbyval)
Definition: makefuncs.c:298
#define OidIsValid(objectId)
Definition: c.h:605
CoercionContext
Definition: primnodes.h:421
int natts
Definition: tupdesc.h:82
bool IsPreferredType(TYPCATEGORY category, Oid type)
int32 typeMod
Definition: primnodes.h:942
CoercionPathType
Definition: parse_coerce.h:24
signed int int32
Definition: c.h:313
Const * makeNullConst(Oid consttype, int32 consttypmod, Oid constcollid)
Definition: makefuncs.c:336
static void hide_coercion_node(Node *node)
Definition: parse_coerce.c:782
#define list_make1(x1)
Definition: pg_list.h:139
int constlen
Definition: primnodes.h:196
Oid consttype
Definition: primnodes.h:193
char TYPCATEGORY
Definition: parse_coerce.h:21
void cancel_parser_errposition_callback(ParseCallbackState *pcbstate)
Definition: parse_node.c:161
bool typeByVal(Type t)
Definition: parse_type.c:590
#define linitial(l)
Definition: pg_list.h:111
#define ObjectIdGetDatum(X)
Definition: postgres.h:490
#define ERROR
Definition: elog.h:43
List * colnames
Definition: primnodes.h:1007
#define DatumGetCString(X)
Definition: postgres.h:549
Node * coerce_to_target_type(ParseState *pstate, Node *expr, Oid exprtype, Oid targettype, int32 targettypmod, CoercionContext ccontext, CoercionForm cformat, int location)
Definition: parse_coerce.c:78
char * typeTypeName(Type t)
Definition: parse_type.c:600
Oid enforce_generic_type_consistency(Oid *actual_arg_types, Oid *declared_arg_types, int nargs, Oid rettype, bool allow_poly)
Datum stringTypeDatum(Type tp, char *string, int32 atttypmod)
Definition: parse_type.c:635
Node * coerce_to_domain(Node *arg, Oid baseTypeId, int32 baseTypeMod, Oid typeId, CoercionContext ccontext, CoercionForm cformat, int location, bool hideInputCoercion)
Definition: parse_coerce.c:663
Oid constcollid
Definition: primnodes.h:195
int location
Definition: primnodes.h:1008
RelabelType * makeRelabelType(Expr *arg, Oid rtype, int32 rtypmod, Oid rcollid, CoercionForm rformat)
Definition: makefuncs.c:401
int errdetail(const char *fmt,...)
Definition: elog.c:873
static Node * build_coercion_expression(Node *node, CoercionPathType pathtype, Oid funcId, Oid targetTypeId, int32 targetTypMod, CoercionContext ccontext, CoercionForm cformat, int location)
Definition: parse_coerce.c:810
static ListCell * list_head(const List *l)
Definition: pg_list.h:77
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:197
static Node * coerce_type_typmod(Node *node, Oid targetTypeId, int32 targetTypMod, CoercionContext ccontext, CoercionForm cformat, int location, bool hideInputCoercion)
Definition: parse_coerce.c:740
Expr * arg
Definition: primnodes.h:815
Expr * elemexpr
Definition: primnodes.h:840
FormData_pg_cast * Form_pg_cast
Definition: pg_cast.h:54
bool check_generic_type_consistency(Oid *actual_arg_types, Oid *declared_arg_types, int nargs)
#define lnext(lc)
Definition: pg_list.h:105
#define ereport(elevel, rest)
Definition: elog.h:122
void setup_parser_errposition_callback(ParseCallbackState *pcbstate, ParseState *pstate, int location)
Definition: parse_node.c:145
Node * coerce_to_common_type(ParseState *pstate, Node *node, Oid targetTypeId, const char *context)
bool IsBinaryCoercible(Oid srctype, Oid targettype)
CoercionPathType find_typmod_coercion_function(Oid typeId, Oid *funcid)
List * lappend(List *list, void *datum)
Definition: list.c:128
#define WARNING
Definition: elog.h:40
void expandRTE(RangeTblEntry *rte, int rtindex, int sublevels_up, int location, bool include_dropped, List **colnames, List **colvars)
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:1112
CoercionForm coerceformat
Definition: primnodes.h:844
int location
Definition: primnodes.h:204
uintptr_t Datum
Definition: postgres.h:365
CoercionForm convertformat
Definition: primnodes.h:867
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:1160
RangeTblEntry * GetRTEByRangeTablePosn(ParseState *pstate, int varno, int sublevels_up)
FormData_pg_proc * Form_pg_proc
Definition: pg_proc.h:132
#define BoolGetDatum(X)
Definition: postgres.h:385
#define InvalidOid
Definition: postgres_ext.h:36
TYPCATEGORY TypeCategory(Oid type)
#define makeNode(_type_)
Definition: nodes.h:565
int location
Definition: primnodes.h:820
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
#define Assert(condition)
Definition: c.h:699
#define lfirst(lc)
Definition: pg_list.h:106
bool typeInheritsFrom(Oid subclassTypeId, Oid superclassTypeId)
Definition: pg_inherits.c:310
#define ISCOMPLEX(typeid)
Definition: parse_type.h:55
static bool typeIsOfTypedTable(Oid reltypeId, Oid reloftypeId)
bool type_is_enum(Oid typid)
Definition: lsyscache.c:2432
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:42
FormData_pg_type * Form_pg_type
Definition: pg_type.h:247
Oid row_typeid
Definition: primnodes.h:992
int parser_errposition(ParseState *pstate, int location)
Definition: parse_node.c:111
Expr * arg
Definition: primnodes.h:881
HeapTuple SearchSysCache2(int cacheId, Datum key1, Datum key2)
Definition: syscache.c:1123
#define type_is_array(typid)
Definition: lsyscache.h:180
#define for_each_cell(cell, initcell)
Definition: pg_list.h:169
#define InvalidAttrNumber
Definition: attnum.h:23
static Node * coerce_record_to_complex(ParseState *pstate, Node *node, Oid targetTypeId, CoercionContext ccontext, CoercionForm cformat, int location)
Definition: parse_coerce.c:978
#define nodeTag(nodeptr)
Definition: nodes.h:522
int32 consttypmod
Definition: primnodes.h:194
CoercionForm coerceformat
Definition: primnodes.h:819
FormData_pg_class * Form_pg_class
Definition: pg_class.h:92
bool can_coerce_type(int nargs, Oid *input_typeids, Oid *target_typeids, CoercionContext ccontext)
Definition: parse_coerce.c:543
#define Int32GetDatum(X)
Definition: postgres.h:462
int errmsg(const char *fmt,...)
Definition: elog.c:797
CoercionPathType find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId, CoercionContext ccontext, Oid *funcid)
int parser_coercion_errposition(ParseState *pstate, int coerce_location, Node *input_expr)
int i
Node * coerce_to_specific_type(ParseState *pstate, Node *node, Oid targetTypeId, const char *constructName)
void * arg
Oid select_common_type(ParseState *pstate, List *exprs, const char *context, Node **which_expr)
#define PG_DETOAST_DATUM(datum)
Definition: fmgr.h:210
int location
Definition: primnodes.h:459
int32 resulttypmod
Definition: primnodes.h:842
#define elog
Definition: elog.h:219
static bool is_complex_array(Oid typid)
Type typeidType(Oid id)
Definition: parse_type.c:559
#define ReleaseTupleDesc(tupdesc)
Definition: tupdesc.h:124
int location
Definition: primnodes.h:883
CoercionForm row_format
Definition: primnodes.h:1006
Oid getBaseType(Oid typid)
Definition: lsyscache.c:2275
CoercionForm
Definition: primnodes.h:437
void get_type_category_preferred(Oid typid, char *typcategory, bool *typispreferred)
Definition: lsyscache.c:2454
Definition: pg_list.h:45
Node * coerce_to_specific_type_typmod(ParseState *pstate, Node *node, Oid targetTypeId, int32 targetTypmod, const char *constructName)
Oid get_range_subtype(Oid rangeOid)
Definition: lsyscache.c:3092
int location
Definition: primnodes.h:800
bool constisnull
Definition: primnodes.h:198
FuncExpr * makeFuncExpr(Oid funcid, Oid rettype, List *args, Oid funccollid, Oid inputcollid, CoercionForm fformat)
Definition: makefuncs.c:519
Node * coerce_to_boolean(ParseState *pstate, Node *node, const char *constructName)