mirror of
https://git.postgresql.org/git/postgresql.git
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1670 lines
43 KiB
C
1670 lines
43 KiB
C
/*-------------------------------------------------------------------------
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*
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* parse_func.c
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* handle function calls in parser
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*
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.101 2001/03/22 03:59:41 momjian Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/genam.h"
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#include "access/heapam.h"
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#include "catalog/catname.h"
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#include "catalog/indexing.h"
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#include "catalog/pg_aggregate.h"
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#include "catalog/pg_inherits.h"
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#include "catalog/pg_proc.h"
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#include "nodes/makefuncs.h"
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#include "parser/parse_agg.h"
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#include "parser/parse_coerce.h"
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#include "parser/parse_expr.h"
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#include "parser/parse_func.h"
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#include "parser/parse_relation.h"
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#include "parser/parse_type.h"
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#include "utils/fmgroids.h"
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#include "utils/lsyscache.h"
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#include "utils/syscache.h"
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static Node *ParseComplexProjection(ParseState *pstate,
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char *funcname,
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Node *first_arg,
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bool *attisset);
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static Oid **argtype_inherit(int nargs, Oid *argtypes);
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static int find_inheritors(Oid relid, Oid **supervec);
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static CandidateList func_get_candidates(char *funcname, int nargs);
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static Oid **gen_cross_product(InhPaths *arginh, int nargs);
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static void make_arguments(ParseState *pstate,
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int nargs,
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List *fargs,
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Oid *input_typeids,
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Oid *function_typeids);
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static int match_argtypes(int nargs,
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Oid *input_typeids,
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CandidateList function_typeids,
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CandidateList *candidates);
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static FieldSelect *setup_field_select(Node *input, char *attname, Oid relid);
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static Oid *func_select_candidate(int nargs, Oid *input_typeids,
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CandidateList candidates);
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static int agg_get_candidates(char *aggname, Oid typeId, CandidateList *candidates);
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static Oid agg_select_candidate(Oid typeid, CandidateList candidates);
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/*
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** ParseNestedFuncOrColumn
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** Given a nested dot expression (i.e. (relation func ... attr), build up
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** a tree with of Iter and Func nodes.
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*/
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Node *
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ParseNestedFuncOrColumn(ParseState *pstate, Attr *attr, int precedence)
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{
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List *mutator_iter;
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Node *retval = NULL;
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if (attr->paramNo != NULL)
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{
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Param *param = (Param *) transformExpr(pstate,
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(Node *) attr->paramNo,
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EXPR_RELATION_FIRST);
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retval = ParseFuncOrColumn(pstate, strVal(lfirst(attr->attrs)),
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makeList1(param),
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false, false,
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precedence);
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}
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else
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{
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Ident *ident = makeNode(Ident);
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ident->name = attr->relname;
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ident->isRel = TRUE;
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retval = ParseFuncOrColumn(pstate, strVal(lfirst(attr->attrs)),
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makeList1(ident),
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false, false,
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precedence);
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}
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/* Do more attributes follow this one? */
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foreach(mutator_iter, lnext(attr->attrs))
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{
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retval = ParseFuncOrColumn(pstate, strVal(lfirst(mutator_iter)),
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makeList1(retval),
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false, false,
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precedence);
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}
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return retval;
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}
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static int
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agg_get_candidates(char *aggname,
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Oid typeId,
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CandidateList *candidates)
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{
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CandidateList current_candidate;
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Relation pg_aggregate_desc;
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HeapScanDesc pg_aggregate_scan;
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HeapTuple tup;
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Form_pg_aggregate agg;
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int ncandidates = 0;
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ScanKeyData aggKey[1];
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*candidates = NULL;
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ScanKeyEntryInitialize(&aggKey[0], 0,
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Anum_pg_aggregate_aggname,
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F_NAMEEQ,
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NameGetDatum(aggname));
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pg_aggregate_desc = heap_openr(AggregateRelationName, AccessShareLock);
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pg_aggregate_scan = heap_beginscan(pg_aggregate_desc,
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0,
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SnapshotSelf, /* ??? */
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1,
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aggKey);
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while (HeapTupleIsValid(tup = heap_getnext(pg_aggregate_scan, 0)))
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{
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agg = (Form_pg_aggregate) GETSTRUCT(tup);
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current_candidate = (CandidateList) palloc(sizeof(struct _CandidateList));
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current_candidate->args = (Oid *) palloc(sizeof(Oid));
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current_candidate->args[0] = agg->aggbasetype;
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current_candidate->next = *candidates;
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*candidates = current_candidate;
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ncandidates++;
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}
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heap_endscan(pg_aggregate_scan);
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heap_close(pg_aggregate_desc, AccessShareLock);
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return ncandidates;
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} /* agg_get_candidates() */
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/* agg_select_candidate()
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*
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* Try to choose only one candidate aggregate function from a list of
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* possible matches. Return value is Oid of input type of aggregate
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* if successful, else InvalidOid.
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*/
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static Oid
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agg_select_candidate(Oid typeid, CandidateList candidates)
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{
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CandidateList current_candidate;
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CandidateList last_candidate;
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Oid current_typeid;
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int ncandidates;
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CATEGORY category,
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current_category;
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/*
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* First look for exact matches or binary compatible matches. (Of
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* course exact matches shouldn't even get here, but anyway.)
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*/
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ncandidates = 0;
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last_candidate = NULL;
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for (current_candidate = candidates;
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current_candidate != NULL;
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current_candidate = current_candidate->next)
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{
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current_typeid = current_candidate->args[0];
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if (current_typeid == typeid
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|| IS_BINARY_COMPATIBLE(current_typeid, typeid))
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{
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last_candidate = current_candidate;
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ncandidates++;
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}
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}
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if (ncandidates == 1)
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return last_candidate->args[0];
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/*
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* If no luck that way, look for candidates which allow coercion and
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* have a preferred type. Keep all candidates if none match.
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*/
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category = TypeCategory(typeid);
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ncandidates = 0;
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last_candidate = NULL;
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for (current_candidate = candidates;
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current_candidate != NULL;
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current_candidate = current_candidate->next)
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{
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current_typeid = current_candidate->args[0];
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current_category = TypeCategory(current_typeid);
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if (current_category == category
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&& IsPreferredType(current_category, current_typeid)
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&& can_coerce_type(1, &typeid, ¤t_typeid))
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{
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/* only one so far? then keep it... */
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if (last_candidate == NULL)
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{
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candidates = current_candidate;
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last_candidate = current_candidate;
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ncandidates = 1;
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}
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/* otherwise, keep this one too... */
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else
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{
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last_candidate->next = current_candidate;
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last_candidate = current_candidate;
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ncandidates++;
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}
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}
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/* otherwise, don't bother keeping this one around... */
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}
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if (last_candidate) /* terminate rebuilt list */
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last_candidate->next = NULL;
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if (ncandidates == 1)
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return candidates->args[0];
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return InvalidOid;
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} /* agg_select_candidate() */
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/*
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* parse function
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*/
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Node *
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ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs,
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bool agg_star, bool agg_distinct,
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int precedence)
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{
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Oid rettype = InvalidOid;
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Oid argrelid = InvalidOid;
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Oid funcid = InvalidOid;
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List *i = NIL;
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Node *first_arg = NULL;
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char *refname;
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Relation rd;
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int nargs = length(fargs);
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Func *funcnode;
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Oid oid_array[FUNC_MAX_ARGS];
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Oid *true_oid_array;
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Node *retval;
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bool retset;
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bool must_be_agg = agg_star || agg_distinct;
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bool could_be_agg;
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bool attisset = false;
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Oid toid = InvalidOid;
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Expr *expr;
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if (fargs)
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{
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first_arg = lfirst(fargs);
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if (first_arg == NULL)
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elog(ERROR, "Function '%s' does not allow NULL input", funcname);
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}
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/*
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* check for projection methods: if function takes one argument, and
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* that argument is a relation, param, or PQ function returning a
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* complex * type, then the function could be a projection.
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*/
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/* We only have one parameter, and it's not got aggregate decoration */
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if (nargs == 1 && !must_be_agg)
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{
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/* Is it a plain Relation name from the parser? */
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if (IsA(first_arg, Ident) &&((Ident *) first_arg)->isRel)
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{
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Ident *ident = (Ident *) first_arg;
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/*
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* first arg is a relation. This could be a projection.
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*/
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refname = ident->name;
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retval = qualifiedNameToVar(pstate, refname, funcname, true);
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if (retval)
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return retval;
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/* else drop through - attr is a set or function */
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}
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else if (ISCOMPLEX(exprType(first_arg)))
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{
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/*
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* Attempt to handle projection of a complex argument. If
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* ParseComplexProjection can't handle the projection, we have
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* to keep going.
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*/
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retval = ParseComplexProjection(pstate,
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funcname,
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first_arg,
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&attisset);
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if (attisset)
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{
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toid = exprType(first_arg);
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rd = heap_openr_nofail(typeidTypeName(toid));
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if (RelationIsValid(rd))
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heap_close(rd, NoLock);
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else
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elog(ERROR, "Type '%s' is not a relation type",
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typeidTypeName(toid));
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argrelid = typeidTypeRelid(toid);
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/*
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* A projection must match an attribute name of the rel.
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*/
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if (get_attnum(argrelid, funcname) == InvalidAttrNumber)
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elog(ERROR, "No such attribute or function '%s'",
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funcname);
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}
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if (retval)
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return retval;
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}
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}
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/*
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* See if it's an aggregate.
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*/
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if (must_be_agg)
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{
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/* We don't presently cope with, eg, foo(DISTINCT x,y) */
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if (nargs != 1)
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elog(ERROR, "Aggregate functions may only have one parameter");
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/* Agg's argument can't be a relation name, either */
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if (IsA(first_arg, Ident) &&((Ident *) first_arg)->isRel)
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elog(ERROR, "Aggregate functions cannot be applied to relation names");
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could_be_agg = true;
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}
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else
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{
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/* Try to parse as an aggregate if above-mentioned checks are OK */
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could_be_agg = (nargs == 1) &&
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!(IsA(first_arg, Ident) &&((Ident *) first_arg)->isRel);
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}
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if (could_be_agg)
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{
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Oid basetype = exprType(lfirst(fargs));
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int ncandidates;
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CandidateList candidates;
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/* try for exact match first... */
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if (SearchSysCacheExists(AGGNAME,
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PointerGetDatum(funcname),
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ObjectIdGetDatum(basetype),
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0, 0))
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return (Node *) ParseAgg(pstate, funcname, basetype,
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fargs, agg_star, agg_distinct,
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precedence);
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/* check for aggregate-that-accepts-any-type (eg, COUNT) */
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if (SearchSysCacheExists(AGGNAME,
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PointerGetDatum(funcname),
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ObjectIdGetDatum(0),
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0, 0))
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return (Node *) ParseAgg(pstate, funcname, 0,
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fargs, agg_star, agg_distinct,
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precedence);
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/*
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* No exact match yet, so see if there is another entry in the
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* aggregate table that is compatible. - thomas 1998-12-05
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*/
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ncandidates = agg_get_candidates(funcname, basetype, &candidates);
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if (ncandidates > 0)
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{
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Oid type;
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type = agg_select_candidate(basetype, candidates);
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if (OidIsValid(type))
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{
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lfirst(fargs) = coerce_type(pstate, lfirst(fargs),
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basetype, type, -1);
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basetype = type;
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return (Node *) ParseAgg(pstate, funcname, basetype,
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fargs, agg_star, agg_distinct,
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precedence);
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}
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else
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{
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/* Multiple possible matches --- give up */
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elog(ERROR, "Unable to select an aggregate function %s(%s)",
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funcname, typeidTypeName(basetype));
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}
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}
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if (must_be_agg)
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{
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/*
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* No matching agg, but we had '*' or DISTINCT, so a plain
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* function could not have been meant.
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*/
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elog(ERROR, "There is no aggregate function %s(%s)",
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funcname, typeidTypeName(basetype));
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}
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}
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/*
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* If we dropped through to here it's really a function (or a set,
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* which is implemented as a function). Extract arg type info and
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* transform relation name arguments into varnodes of the appropriate
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* form.
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*/
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MemSet(oid_array, 0, FUNC_MAX_ARGS * sizeof(Oid));
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nargs = 0;
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foreach(i, fargs)
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{
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Node *arg = lfirst(i);
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if (IsA(arg, Ident) &&((Ident *) arg)->isRel)
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{
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RangeTblEntry *rte;
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int vnum;
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Node *rteorjoin;
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int sublevels_up;
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/*
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* a relation
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*/
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refname = ((Ident *) arg)->name;
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rteorjoin = refnameRangeOrJoinEntry(pstate, refname,
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&sublevels_up);
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if (rteorjoin == NULL)
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rte = addImplicitRTE(pstate, refname);
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else if (IsA(rteorjoin, RangeTblEntry))
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rte = (RangeTblEntry *) rteorjoin;
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else if (IsA(rteorjoin, JoinExpr))
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{
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/*
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* We have f(x) or more likely x.f where x is a join and f
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* is not one of the attribute names of the join (else
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* we'd have recognized it above). We don't support
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* functions on join tuples (since we don't have a named
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* type for the join tuples), so error out.
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*/
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elog(ERROR, "No such attribute or function %s.%s",
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refname, funcname);
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rte = NULL; /* keep compiler quiet */
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}
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else
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{
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elog(ERROR, "ParseFuncOrColumn: unexpected node type %d",
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nodeTag(rteorjoin));
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rte = NULL; /* keep compiler quiet */
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}
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vnum = RTERangeTablePosn(pstate, rte, &sublevels_up);
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/*
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* for func(relname), the param to the function is the tuple
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* under consideration. We build a special VarNode to reflect
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* this -- it has varno set to the correct range table entry,
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* but has varattno == 0 to signal that the whole tuple is the
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* argument. Also, it has typmod set to sizeof(Pointer) to
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* signal that the runtime representation will be a pointer
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* not an Oid.
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*/
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if (rte->relname == NULL)
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{
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/* Here, we have an unrecognized attribute of a sub-select */
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elog(ERROR, "No such attribute or function %s.%s",
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refname, funcname);
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}
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toid = typenameTypeId(rte->relname);
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/* replace it in the arg list */
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lfirst(i) = makeVar(vnum,
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InvalidAttrNumber,
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toid,
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sizeof(Pointer),
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sublevels_up);
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}
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else if (!attisset)
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toid = exprType(arg);
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else
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{
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/* if attisset is true, we already set toid for the single arg */
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}
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/*
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* Most of the rest of the parser just assumes that functions do
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* not have more than FUNC_MAX_ARGS parameters. We have to test
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* here to protect against array overruns, etc.
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*/
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if (nargs >= FUNC_MAX_ARGS)
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elog(ERROR, "Cannot pass more than %d arguments to a function",
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FUNC_MAX_ARGS);
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oid_array[nargs++] = toid;
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}
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|
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/*
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* func_get_detail looks up the function in the catalogs, does
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* disambiguation for polymorphic functions, handles inheritance, and
|
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* returns the funcid and type and set or singleton status of the
|
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* function's return value. it also returns the true argument types
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* to the function. if func_get_detail returns true, the function
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* exists. otherwise, there was an error.
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*/
|
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if (attisset)
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{ /* we know all of these fields already */
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|
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/*
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* We create a funcnode with a placeholder function seteval(). At
|
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* runtime, seteval() will execute the function identified by the
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* funcid it receives as parameter.
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*
|
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* Example: retrieve (emp.mgr.name). The plan for this will scan the
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* emp relation, projecting out the mgr attribute, which is a
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* funcid. This function is then called (via seteval()) and "name"
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* is projected from its result.
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|
*/
|
|
funcid = F_SETEVAL;
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rettype = toid;
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retset = true;
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true_oid_array = oid_array;
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}
|
|
else
|
|
{
|
|
bool exists;
|
|
|
|
exists = func_get_detail(funcname, nargs, oid_array, &funcid,
|
|
&rettype, &retset, &true_oid_array);
|
|
if (!exists)
|
|
{
|
|
|
|
/*
|
|
* If we can't find a function (or can't find a unique
|
|
* function), see if this is really a type-coercion request:
|
|
* single-argument function call where the function name is a
|
|
* type name. If so, and if we can do the coercion trivially,
|
|
* just go ahead and do it without requiring there to be a
|
|
* real function for it.
|
|
*
|
|
* "Trivial" coercions are ones that involve binary-compatible
|
|
* types and ones that are coercing a previously-unknown-type
|
|
* literal constant to a specific type.
|
|
*
|
|
* DO NOT try to generalize this code to nontrivial coercions,
|
|
* because you'll just set up an infinite recursion between
|
|
* this routine and coerce_type! We have already failed to
|
|
* find a suitable "real" coercion function, so we have to
|
|
* fail unless this is a coercion that coerce_type can handle
|
|
* by itself. Make sure this code stays in sync with what
|
|
* coerce_type does!
|
|
*/
|
|
if (nargs == 1)
|
|
{
|
|
Oid targetType;
|
|
|
|
targetType = GetSysCacheOid(TYPENAME,
|
|
PointerGetDatum(funcname),
|
|
0, 0, 0);
|
|
if (OidIsValid(targetType))
|
|
{
|
|
Oid sourceType = oid_array[0];
|
|
Node *arg1 = lfirst(fargs);
|
|
|
|
if ((sourceType == UNKNOWNOID && IsA(arg1, Const)) ||
|
|
sourceType == targetType ||
|
|
IS_BINARY_COMPATIBLE(sourceType, targetType))
|
|
{
|
|
|
|
/*
|
|
* Ah-hah, we can do it as a trivial coercion.
|
|
* coerce_type can handle these cases, so why
|
|
* duplicate code...
|
|
*/
|
|
return coerce_type(pstate, arg1,
|
|
sourceType, targetType, -1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Oops. Time to die.
|
|
*
|
|
* If there is a single argument of complex type, we might be
|
|
* dealing with the PostQuel notation rel.function instead of
|
|
* the more usual function(rel). Give a nonspecific error
|
|
* message that will cover both cases.
|
|
*/
|
|
if (nargs == 1)
|
|
{
|
|
Type tp = typeidType(oid_array[0]);
|
|
|
|
if (typeTypeFlag(tp) == 'c')
|
|
elog(ERROR, "No such attribute or function '%s'",
|
|
funcname);
|
|
ReleaseSysCache(tp);
|
|
}
|
|
|
|
/* Else generate a detailed complaint */
|
|
func_error(NULL, funcname, nargs, oid_array,
|
|
"Unable to identify a function that satisfies the "
|
|
"given argument types"
|
|
"\n\tYou may need to add explicit typecasts");
|
|
}
|
|
}
|
|
|
|
/* got it */
|
|
funcnode = makeNode(Func);
|
|
funcnode->funcid = funcid;
|
|
funcnode->functype = rettype;
|
|
funcnode->func_fcache = NULL;
|
|
|
|
/* perform the necessary typecasting of arguments */
|
|
make_arguments(pstate, nargs, fargs, oid_array, true_oid_array);
|
|
|
|
expr = makeNode(Expr);
|
|
expr->typeOid = rettype;
|
|
expr->opType = FUNC_EXPR;
|
|
expr->oper = (Node *) funcnode;
|
|
expr->args = fargs;
|
|
retval = (Node *) expr;
|
|
|
|
/*
|
|
* For sets, we want to project out the desired attribute of the
|
|
* tuples.
|
|
*/
|
|
if (attisset)
|
|
{
|
|
FieldSelect *fselect;
|
|
|
|
fselect = setup_field_select(retval, funcname, argrelid);
|
|
rettype = fselect->resulttype;
|
|
retval = (Node *) fselect;
|
|
}
|
|
|
|
/*
|
|
* if the function returns a set of values, then we need to iterate
|
|
* over all the returned values in the executor, so we stick an iter
|
|
* node here. if it returns a singleton, then we don't need the iter
|
|
* node.
|
|
*/
|
|
|
|
if (retset)
|
|
{
|
|
Iter *iter = makeNode(Iter);
|
|
|
|
iter->itertype = rettype;
|
|
iter->iterexpr = retval;
|
|
retval = (Node *) iter;
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
|
|
/* func_get_candidates()
|
|
* get a list of all argument type vectors for which a function named
|
|
* funcname taking nargs arguments exists
|
|
*/
|
|
static CandidateList
|
|
func_get_candidates(char *funcname, int nargs)
|
|
{
|
|
Relation heapRelation;
|
|
Relation idesc;
|
|
ScanKeyData skey;
|
|
HeapTupleData tuple;
|
|
IndexScanDesc sd;
|
|
RetrieveIndexResult indexRes;
|
|
Form_pg_proc pgProcP;
|
|
CandidateList candidates = NULL;
|
|
CandidateList current_candidate;
|
|
int i;
|
|
|
|
heapRelation = heap_openr(ProcedureRelationName, AccessShareLock);
|
|
ScanKeyEntryInitialize(&skey,
|
|
(bits16) 0x0,
|
|
(AttrNumber) Anum_pg_proc_proname,
|
|
(RegProcedure) F_NAMEEQ,
|
|
(Datum) funcname);
|
|
|
|
idesc = index_openr(ProcedureNameIndex);
|
|
|
|
sd = index_beginscan(idesc, false, 1, &skey);
|
|
|
|
do
|
|
{
|
|
indexRes = index_getnext(sd, ForwardScanDirection);
|
|
if (indexRes)
|
|
{
|
|
Buffer buffer;
|
|
|
|
tuple.t_datamcxt = NULL;
|
|
tuple.t_data = NULL;
|
|
tuple.t_self = indexRes->heap_iptr;
|
|
heap_fetch(heapRelation, SnapshotNow, &tuple, &buffer);
|
|
pfree(indexRes);
|
|
if (tuple.t_data != NULL)
|
|
{
|
|
pgProcP = (Form_pg_proc) GETSTRUCT(&tuple);
|
|
if (pgProcP->pronargs == nargs)
|
|
{
|
|
current_candidate = (CandidateList)
|
|
palloc(sizeof(struct _CandidateList));
|
|
current_candidate->args = (Oid *)
|
|
palloc(FUNC_MAX_ARGS * sizeof(Oid));
|
|
MemSet(current_candidate->args, 0, FUNC_MAX_ARGS * sizeof(Oid));
|
|
for (i = 0; i < nargs; i++)
|
|
current_candidate->args[i] = pgProcP->proargtypes[i];
|
|
|
|
current_candidate->next = candidates;
|
|
candidates = current_candidate;
|
|
}
|
|
ReleaseBuffer(buffer);
|
|
}
|
|
}
|
|
} while (indexRes);
|
|
|
|
index_endscan(sd);
|
|
index_close(idesc);
|
|
heap_close(heapRelation, AccessShareLock);
|
|
|
|
return candidates;
|
|
}
|
|
|
|
|
|
/* match_argtypes()
|
|
* Given a list of possible typeid arrays to a function and an array of
|
|
* input typeids, produce a shortlist of those function typeid arrays
|
|
* that match the input typeids (either exactly or by coercion), and
|
|
* return the number of such arrays
|
|
*/
|
|
static int
|
|
match_argtypes(int nargs,
|
|
Oid *input_typeids,
|
|
CandidateList function_typeids,
|
|
CandidateList *candidates) /* return value */
|
|
{
|
|
CandidateList current_candidate;
|
|
CandidateList matching_candidate;
|
|
Oid *current_typeids;
|
|
int ncandidates = 0;
|
|
|
|
*candidates = NULL;
|
|
|
|
for (current_candidate = function_typeids;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
if (can_coerce_type(nargs, input_typeids, current_typeids))
|
|
{
|
|
matching_candidate = (CandidateList)
|
|
palloc(sizeof(struct _CandidateList));
|
|
matching_candidate->args = current_typeids;
|
|
matching_candidate->next = *candidates;
|
|
*candidates = matching_candidate;
|
|
ncandidates++;
|
|
}
|
|
}
|
|
|
|
return ncandidates;
|
|
} /* match_argtypes() */
|
|
|
|
|
|
/* func_select_candidate()
|
|
* Given the input argtype array and more than one candidate
|
|
* for the function argtype array, attempt to resolve the conflict.
|
|
* Returns the selected argtype array if the conflict can be resolved,
|
|
* otherwise returns NULL.
|
|
*
|
|
* By design, this is pretty similar to oper_select_candidate in parse_oper.c.
|
|
* However, the calling convention is a little different: we assume the caller
|
|
* already pruned away "candidates" that aren't actually coercion-compatible
|
|
* with the input types, whereas oper_select_candidate must do that itself.
|
|
*/
|
|
static Oid *
|
|
func_select_candidate(int nargs,
|
|
Oid *input_typeids,
|
|
CandidateList candidates)
|
|
{
|
|
CandidateList current_candidate;
|
|
CandidateList last_candidate;
|
|
Oid *current_typeids;
|
|
Oid current_type;
|
|
int i;
|
|
int ncandidates;
|
|
int nbestMatch,
|
|
nmatch;
|
|
CATEGORY slot_category[FUNC_MAX_ARGS],
|
|
current_category;
|
|
bool slot_has_preferred_type[FUNC_MAX_ARGS];
|
|
bool resolved_unknowns;
|
|
|
|
/*
|
|
* Run through all candidates and keep those with the most matches on
|
|
* exact types. Keep all candidates if none match.
|
|
*/
|
|
ncandidates = 0;
|
|
nbestMatch = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
nmatch = 0;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_typeids[i] != UNKNOWNOID &&
|
|
current_typeids[i] == input_typeids[i])
|
|
nmatch++;
|
|
}
|
|
|
|
/* take this one as the best choice so far? */
|
|
if ((nmatch > nbestMatch) || (last_candidate == NULL))
|
|
{
|
|
nbestMatch = nmatch;
|
|
candidates = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates = 1;
|
|
}
|
|
/* no worse than the last choice, so keep this one too? */
|
|
else if (nmatch == nbestMatch)
|
|
{
|
|
last_candidate->next = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
/* otherwise, don't bother keeping this one... */
|
|
}
|
|
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
|
|
if (ncandidates == 1)
|
|
return candidates->args;
|
|
|
|
/*
|
|
* Still too many candidates? Run through all candidates and keep
|
|
* those with the most matches on exact types + binary-compatible
|
|
* types. Keep all candidates if none match.
|
|
*/
|
|
ncandidates = 0;
|
|
nbestMatch = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
nmatch = 0;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_typeids[i] != UNKNOWNOID)
|
|
{
|
|
if (current_typeids[i] == input_typeids[i] ||
|
|
IS_BINARY_COMPATIBLE(current_typeids[i],
|
|
input_typeids[i]))
|
|
nmatch++;
|
|
}
|
|
}
|
|
|
|
/* take this one as the best choice so far? */
|
|
if ((nmatch > nbestMatch) || (last_candidate == NULL))
|
|
{
|
|
nbestMatch = nmatch;
|
|
candidates = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates = 1;
|
|
}
|
|
/* no worse than the last choice, so keep this one too? */
|
|
else if (nmatch == nbestMatch)
|
|
{
|
|
last_candidate->next = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
/* otherwise, don't bother keeping this one... */
|
|
}
|
|
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
|
|
if (ncandidates == 1)
|
|
return candidates->args;
|
|
|
|
/*
|
|
* Still too many candidates? Now look for candidates which are
|
|
* preferred types at the args that will require coercion. Keep all
|
|
* candidates if none match.
|
|
*/
|
|
ncandidates = 0;
|
|
nbestMatch = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
nmatch = 0;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_typeids[i] != UNKNOWNOID)
|
|
{
|
|
current_category = TypeCategory(current_typeids[i]);
|
|
if (current_typeids[i] == input_typeids[i] ||
|
|
IsPreferredType(current_category, current_typeids[i]))
|
|
nmatch++;
|
|
}
|
|
}
|
|
|
|
if ((nmatch > nbestMatch) || (last_candidate == NULL))
|
|
{
|
|
nbestMatch = nmatch;
|
|
candidates = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates = 1;
|
|
}
|
|
else if (nmatch == nbestMatch)
|
|
{
|
|
last_candidate->next = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
}
|
|
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
|
|
if (ncandidates == 1)
|
|
return candidates->args;
|
|
|
|
/*
|
|
* Still too many candidates? Try assigning types for the unknown
|
|
* columns.
|
|
*
|
|
* We do this by examining each unknown argument position to see if we
|
|
* can determine a "type category" for it. If any candidate has an
|
|
* input datatype of STRING category, use STRING category (this bias
|
|
* towards STRING is appropriate since unknown-type literals look like
|
|
* strings). Otherwise, if all the candidates agree on the type
|
|
* category of this argument position, use that category. Otherwise,
|
|
* fail because we cannot determine a category.
|
|
*
|
|
* If we are able to determine a type category, also notice whether any
|
|
* of the candidates takes a preferred datatype within the category.
|
|
*
|
|
* Having completed this examination, remove candidates that accept the
|
|
* wrong category at any unknown position. Also, if at least one
|
|
* candidate accepted a preferred type at a position, remove
|
|
* candidates that accept non-preferred types.
|
|
*
|
|
* If we are down to one candidate at the end, we win.
|
|
*/
|
|
resolved_unknowns = false;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
bool have_conflict;
|
|
|
|
if (input_typeids[i] != UNKNOWNOID)
|
|
continue;
|
|
resolved_unknowns = true; /* assume we can do it */
|
|
slot_category[i] = INVALID_TYPE;
|
|
slot_has_preferred_type[i] = false;
|
|
have_conflict = false;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
current_type = current_typeids[i];
|
|
current_category = TypeCategory(current_type);
|
|
if (slot_category[i] == INVALID_TYPE)
|
|
{
|
|
/* first candidate */
|
|
slot_category[i] = current_category;
|
|
slot_has_preferred_type[i] =
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else if (current_category == slot_category[i])
|
|
{
|
|
/* more candidates in same category */
|
|
slot_has_preferred_type[i] |=
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else
|
|
{
|
|
/* category conflict! */
|
|
if (current_category == STRING_TYPE)
|
|
{
|
|
/* STRING always wins if available */
|
|
slot_category[i] = current_category;
|
|
slot_has_preferred_type[i] =
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else
|
|
{
|
|
|
|
/*
|
|
* Remember conflict, but keep going (might find
|
|
* STRING)
|
|
*/
|
|
have_conflict = true;
|
|
}
|
|
}
|
|
}
|
|
if (have_conflict && slot_category[i] != STRING_TYPE)
|
|
{
|
|
/* Failed to resolve category conflict at this position */
|
|
resolved_unknowns = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (resolved_unknowns)
|
|
{
|
|
/* Strip non-matching candidates */
|
|
ncandidates = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
bool keepit = true;
|
|
|
|
current_typeids = current_candidate->args;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_typeids[i] != UNKNOWNOID)
|
|
continue;
|
|
current_type = current_typeids[i];
|
|
current_category = TypeCategory(current_type);
|
|
if (current_category != slot_category[i])
|
|
{
|
|
keepit = false;
|
|
break;
|
|
}
|
|
if (slot_has_preferred_type[i] &&
|
|
!IsPreferredType(current_category, current_type))
|
|
{
|
|
keepit = false;
|
|
break;
|
|
}
|
|
}
|
|
if (keepit)
|
|
{
|
|
/* keep this candidate */
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
else
|
|
{
|
|
/* forget this candidate */
|
|
if (last_candidate)
|
|
last_candidate->next = current_candidate->next;
|
|
else
|
|
candidates = current_candidate->next;
|
|
}
|
|
}
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
}
|
|
|
|
if (ncandidates == 1)
|
|
return candidates->args;
|
|
|
|
return NULL; /* failed to determine a unique candidate */
|
|
} /* func_select_candidate() */
|
|
|
|
|
|
/* func_get_detail()
|
|
* Find the named function in the system catalogs.
|
|
*
|
|
* Attempt to find the named function in the system catalogs with
|
|
* arguments exactly as specified, so that the normal case
|
|
* (exact match) is as quick as possible.
|
|
*
|
|
* If an exact match isn't found:
|
|
* 1) get a vector of all possible input arg type arrays constructed
|
|
* from the superclasses of the original input arg types
|
|
* 2) get a list of all possible argument type arrays to the function
|
|
* with given name and number of arguments
|
|
* 3) for each input arg type array from vector #1:
|
|
* a) find how many of the function arg type arrays from list #2
|
|
* it can be coerced to
|
|
* b) if the answer is one, we have our function
|
|
* c) if the answer is more than one, attempt to resolve the conflict
|
|
* d) if the answer is zero, try the next array from vector #1
|
|
*/
|
|
bool
|
|
func_get_detail(char *funcname,
|
|
int nargs,
|
|
Oid *argtypes,
|
|
Oid *funcid, /* return value */
|
|
Oid *rettype, /* return value */
|
|
bool *retset, /* return value */
|
|
Oid **true_typeids) /* return value */
|
|
{
|
|
HeapTuple ftup;
|
|
|
|
/* attempt to find with arguments exactly as specified... */
|
|
ftup = SearchSysCache(PROCNAME,
|
|
PointerGetDatum(funcname),
|
|
Int32GetDatum(nargs),
|
|
PointerGetDatum(argtypes),
|
|
0);
|
|
|
|
if (HeapTupleIsValid(ftup))
|
|
{
|
|
/* given argument types are the right ones */
|
|
*true_typeids = argtypes;
|
|
}
|
|
else
|
|
{
|
|
|
|
/*
|
|
* didn't find an exact match, so now try to match up
|
|
* candidates...
|
|
*/
|
|
CandidateList function_typeids;
|
|
|
|
function_typeids = func_get_candidates(funcname, nargs);
|
|
|
|
/* found something, so let's look through them... */
|
|
if (function_typeids != NULL)
|
|
{
|
|
Oid **input_typeid_vector = NULL;
|
|
Oid *current_input_typeids;
|
|
|
|
/*
|
|
* First we will search with the given argtypes, then with
|
|
* variants based on replacing complex types with their
|
|
* inheritance ancestors. Stop as soon as any match is found.
|
|
*/
|
|
current_input_typeids = argtypes;
|
|
|
|
do
|
|
{
|
|
CandidateList current_function_typeids;
|
|
int ncandidates;
|
|
|
|
ncandidates = match_argtypes(nargs, current_input_typeids,
|
|
function_typeids,
|
|
¤t_function_typeids);
|
|
|
|
/* one match only? then run with it... */
|
|
if (ncandidates == 1)
|
|
{
|
|
*true_typeids = current_function_typeids->args;
|
|
ftup = SearchSysCache(PROCNAME,
|
|
PointerGetDatum(funcname),
|
|
Int32GetDatum(nargs),
|
|
PointerGetDatum(*true_typeids),
|
|
0);
|
|
Assert(HeapTupleIsValid(ftup));
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* multiple candidates? then better decide or throw an
|
|
* error...
|
|
*/
|
|
if (ncandidates > 1)
|
|
{
|
|
*true_typeids = func_select_candidate(nargs,
|
|
current_input_typeids,
|
|
current_function_typeids);
|
|
|
|
if (*true_typeids != NULL)
|
|
{
|
|
/* was able to choose a best candidate */
|
|
ftup = SearchSysCache(PROCNAME,
|
|
PointerGetDatum(funcname),
|
|
Int32GetDatum(nargs),
|
|
PointerGetDatum(*true_typeids),
|
|
0);
|
|
Assert(HeapTupleIsValid(ftup));
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* otherwise, ambiguous function call, so fail by
|
|
* exiting loop with ftup still NULL.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* No match here, so try the next inherited type vector.
|
|
* First time through, we need to compute the list of
|
|
* vectors.
|
|
*/
|
|
if (input_typeid_vector == NULL)
|
|
input_typeid_vector = argtype_inherit(nargs, argtypes);
|
|
|
|
current_input_typeids = *input_typeid_vector++;
|
|
}
|
|
while (current_input_typeids != NULL);
|
|
}
|
|
}
|
|
|
|
if (HeapTupleIsValid(ftup))
|
|
{
|
|
Form_pg_proc pform = (Form_pg_proc) GETSTRUCT(ftup);
|
|
|
|
*funcid = ftup->t_data->t_oid;
|
|
*rettype = pform->prorettype;
|
|
*retset = pform->proretset;
|
|
ReleaseSysCache(ftup);
|
|
return true;
|
|
}
|
|
return false;
|
|
} /* func_get_detail() */
|
|
|
|
/*
|
|
* argtype_inherit() -- Construct an argtype vector reflecting the
|
|
* inheritance properties of the supplied argv.
|
|
*
|
|
* This function is used to disambiguate among functions with the
|
|
* same name but different signatures. It takes an array of input
|
|
* type ids. For each type id in the array that's a complex type
|
|
* (a class), it walks up the inheritance tree, finding all
|
|
* superclasses of that type. A vector of new Oid type arrays
|
|
* is returned to the caller, reflecting the structure of the
|
|
* inheritance tree above the supplied arguments.
|
|
*
|
|
* The order of this vector is as follows: all superclasses of the
|
|
* rightmost complex class are explored first. The exploration
|
|
* continues from right to left. This policy means that we favor
|
|
* keeping the leftmost argument type as low in the inheritance tree
|
|
* as possible. This is intentional; it is exactly what we need to
|
|
* do for method dispatch. The last type array we return is all
|
|
* zeroes. This will match any functions for which return types are
|
|
* not defined. There are lots of these (mostly builtins) in the
|
|
* catalogs.
|
|
*/
|
|
static Oid **
|
|
argtype_inherit(int nargs, Oid *argtypes)
|
|
{
|
|
Oid relid;
|
|
int i;
|
|
InhPaths arginh[FUNC_MAX_ARGS];
|
|
|
|
for (i = 0; i < FUNC_MAX_ARGS; i++)
|
|
{
|
|
if (i < nargs)
|
|
{
|
|
arginh[i].self = argtypes[i];
|
|
if ((relid = typeidTypeRelid(argtypes[i])) != InvalidOid)
|
|
arginh[i].nsupers = find_inheritors(relid, &(arginh[i].supervec));
|
|
else
|
|
{
|
|
arginh[i].nsupers = 0;
|
|
arginh[i].supervec = (Oid *) NULL;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
arginh[i].self = InvalidOid;
|
|
arginh[i].nsupers = 0;
|
|
arginh[i].supervec = (Oid *) NULL;
|
|
}
|
|
}
|
|
|
|
/* return an ordered cross-product of the classes involved */
|
|
return gen_cross_product(arginh, nargs);
|
|
}
|
|
|
|
static int
|
|
find_inheritors(Oid relid, Oid **supervec)
|
|
{
|
|
Relation inhrel;
|
|
HeapScanDesc inhscan;
|
|
ScanKeyData skey;
|
|
HeapTuple inhtup;
|
|
Oid *relidvec;
|
|
int nvisited;
|
|
List *visited,
|
|
*queue;
|
|
List *elt;
|
|
bool newrelid;
|
|
|
|
nvisited = 0;
|
|
queue = NIL;
|
|
visited = NIL;
|
|
|
|
inhrel = heap_openr(InheritsRelationName, AccessShareLock);
|
|
|
|
/*
|
|
* Use queue to do a breadth-first traversal of the inheritance graph
|
|
* from the relid supplied up to the root. At the top of the loop,
|
|
* relid is the OID of the reltype to check next, queue is the list of
|
|
* pending rels to check after this one, and visited is the list of
|
|
* relids we need to output.
|
|
*/
|
|
do
|
|
{
|
|
/* find all types this relid inherits from, and add them to queue */
|
|
|
|
ScanKeyEntryInitialize(&skey, 0x0, Anum_pg_inherits_inhrelid,
|
|
F_OIDEQ,
|
|
ObjectIdGetDatum(relid));
|
|
|
|
inhscan = heap_beginscan(inhrel, 0, SnapshotNow, 1, &skey);
|
|
|
|
while (HeapTupleIsValid(inhtup = heap_getnext(inhscan, 0)))
|
|
{
|
|
Form_pg_inherits inh = (Form_pg_inherits) GETSTRUCT(inhtup);
|
|
|
|
queue = lappendi(queue, inh->inhparent);
|
|
}
|
|
|
|
heap_endscan(inhscan);
|
|
|
|
/* pull next unvisited relid off the queue */
|
|
|
|
newrelid = false;
|
|
while (queue != NIL)
|
|
{
|
|
relid = lfirsti(queue);
|
|
queue = lnext(queue);
|
|
if (!intMember(relid, visited))
|
|
{
|
|
newrelid = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (newrelid)
|
|
{
|
|
visited = lappendi(visited, relid);
|
|
nvisited++;
|
|
}
|
|
} while (newrelid);
|
|
|
|
heap_close(inhrel, AccessShareLock);
|
|
|
|
if (nvisited > 0)
|
|
{
|
|
relidvec = (Oid *) palloc(nvisited * sizeof(Oid));
|
|
*supervec = relidvec;
|
|
|
|
foreach(elt, visited)
|
|
{
|
|
/* return the type id, rather than the relation id */
|
|
Relation rd;
|
|
Oid trelid;
|
|
|
|
relid = lfirsti(elt);
|
|
rd = heap_open(relid, NoLock);
|
|
trelid = typenameTypeId(RelationGetRelationName(rd));
|
|
heap_close(rd, NoLock);
|
|
*relidvec++ = trelid;
|
|
}
|
|
}
|
|
else
|
|
*supervec = (Oid *) NULL;
|
|
|
|
freeList(visited);
|
|
|
|
/*
|
|
* there doesn't seem to be any equally easy way to release the queue
|
|
* list cells, but since they're palloc'd space it's not critical.
|
|
*/
|
|
|
|
return nvisited;
|
|
}
|
|
|
|
static Oid **
|
|
gen_cross_product(InhPaths *arginh, int nargs)
|
|
{
|
|
int nanswers;
|
|
Oid **result,
|
|
**iter;
|
|
Oid *oneres;
|
|
int i,
|
|
j;
|
|
int cur[FUNC_MAX_ARGS];
|
|
|
|
nanswers = 1;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
nanswers *= (arginh[i].nsupers + 2);
|
|
cur[i] = 0;
|
|
}
|
|
|
|
iter = result = (Oid **) palloc(sizeof(Oid *) * nanswers);
|
|
|
|
/* compute the cross product from right to left */
|
|
for (;;)
|
|
{
|
|
oneres = (Oid *) palloc(FUNC_MAX_ARGS * sizeof(Oid));
|
|
MemSet(oneres, 0, FUNC_MAX_ARGS * sizeof(Oid));
|
|
|
|
for (i = nargs - 1; i >= 0 && cur[i] > arginh[i].nsupers; i--)
|
|
continue;
|
|
|
|
/* if we're done, terminate with NULL pointer */
|
|
if (i < 0)
|
|
{
|
|
*iter = NULL;
|
|
return result;
|
|
}
|
|
|
|
/* no, increment this column and zero the ones after it */
|
|
cur[i] = cur[i] + 1;
|
|
for (j = nargs - 1; j > i; j--)
|
|
cur[j] = 0;
|
|
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (cur[i] == 0)
|
|
oneres[i] = arginh[i].self;
|
|
else if (cur[i] > arginh[i].nsupers)
|
|
oneres[i] = 0; /* wild card */
|
|
else
|
|
oneres[i] = arginh[i].supervec[cur[i] - 1];
|
|
}
|
|
|
|
*iter++ = oneres;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Given two type OIDs, determine whether the first is a complex type
|
|
* (class type) that inherits from the second.
|
|
*/
|
|
bool
|
|
typeInheritsFrom(Oid subclassTypeId, Oid superclassTypeId)
|
|
{
|
|
Oid relid;
|
|
Oid *supervec;
|
|
int nsupers,
|
|
i;
|
|
bool result;
|
|
|
|
if (!ISCOMPLEX(subclassTypeId) || !ISCOMPLEX(superclassTypeId))
|
|
return false;
|
|
relid = typeidTypeRelid(subclassTypeId);
|
|
if (relid == InvalidOid)
|
|
return false;
|
|
nsupers = find_inheritors(relid, &supervec);
|
|
result = false;
|
|
for (i = 0; i < nsupers; i++)
|
|
{
|
|
if (supervec[i] == superclassTypeId)
|
|
{
|
|
result = true;
|
|
break;
|
|
}
|
|
}
|
|
if (supervec)
|
|
pfree(supervec);
|
|
return result;
|
|
}
|
|
|
|
|
|
/* make_arguments()
|
|
* Given the number and types of arguments to a function, and the
|
|
* actual arguments and argument types, do the necessary typecasting.
|
|
*/
|
|
static void
|
|
make_arguments(ParseState *pstate,
|
|
int nargs,
|
|
List *fargs,
|
|
Oid *input_typeids,
|
|
Oid *function_typeids)
|
|
{
|
|
List *current_fargs;
|
|
int i;
|
|
|
|
for (i = 0, current_fargs = fargs;
|
|
i < nargs;
|
|
i++, current_fargs = lnext(current_fargs))
|
|
{
|
|
/* types don't match? then force coercion using a function call... */
|
|
if (input_typeids[i] != function_typeids[i])
|
|
{
|
|
lfirst(current_fargs) = coerce_type(pstate,
|
|
lfirst(current_fargs),
|
|
input_typeids[i],
|
|
function_typeids[i], -1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** setup_field_select
|
|
** Build a FieldSelect node that says which attribute to project to.
|
|
** This routine is called by ParseFuncOrColumn() when we have found
|
|
** a projection on a function result or parameter.
|
|
*/
|
|
static FieldSelect *
|
|
setup_field_select(Node *input, char *attname, Oid relid)
|
|
{
|
|
FieldSelect *fselect = makeNode(FieldSelect);
|
|
AttrNumber attno;
|
|
|
|
attno = get_attnum(relid, attname);
|
|
|
|
fselect->arg = input;
|
|
fselect->fieldnum = attno;
|
|
fselect->resulttype = get_atttype(relid, attno);
|
|
fselect->resulttypmod = get_atttypmod(relid, attno);
|
|
|
|
return fselect;
|
|
}
|
|
|
|
/*
|
|
* ParseComplexProjection -
|
|
* handles function calls with a single argument that is of complex type.
|
|
* This routine returns NULL if it can't handle the projection (eg. sets).
|
|
*/
|
|
static Node *
|
|
ParseComplexProjection(ParseState *pstate,
|
|
char *funcname,
|
|
Node *first_arg,
|
|
bool *attisset)
|
|
{
|
|
Oid argtype;
|
|
Oid argrelid;
|
|
FieldSelect *fselect;
|
|
|
|
switch (nodeTag(first_arg))
|
|
{
|
|
case T_Iter:
|
|
{
|
|
Iter *iter = (Iter *) first_arg;
|
|
|
|
/*
|
|
* If the argument of the Iter returns a tuple, funcname
|
|
* may be a projection. If so, we stick the FieldSelect
|
|
* *inside* the Iter --- this is klugy, but necessary
|
|
* because ExecTargetList() currently does the right thing
|
|
* only when the Iter node is at the top level of a
|
|
* targetlist item.
|
|
*/
|
|
argtype = iter->itertype;
|
|
argrelid = typeidTypeRelid(argtype);
|
|
if (argrelid &&
|
|
get_attnum(argrelid, funcname) != InvalidAttrNumber)
|
|
{
|
|
fselect = setup_field_select(iter->iterexpr,
|
|
funcname, argrelid);
|
|
iter->iterexpr = (Node *) fselect;
|
|
iter->itertype = fselect->resulttype;
|
|
return (Node *) iter;
|
|
}
|
|
break;
|
|
}
|
|
case T_Var:
|
|
{
|
|
|
|
/*
|
|
* The argument is a set, so this is either a projection
|
|
* or a function call on this set.
|
|
*/
|
|
*attisset = true;
|
|
break;
|
|
}
|
|
case T_Expr:
|
|
{
|
|
Expr *expr = (Expr *) first_arg;
|
|
Func *funcnode;
|
|
|
|
if (expr->opType != FUNC_EXPR)
|
|
break;
|
|
|
|
/*
|
|
* If the argument is a function returning a tuple,
|
|
* funcname may be a projection
|
|
*/
|
|
funcnode = (Func *) expr->oper;
|
|
argtype = funcnode->functype;
|
|
argrelid = typeidTypeRelid(argtype);
|
|
if (argrelid &&
|
|
get_attnum(argrelid, funcname) != InvalidAttrNumber)
|
|
{
|
|
fselect = setup_field_select((Node *) expr,
|
|
funcname, argrelid);
|
|
return (Node *) fselect;
|
|
}
|
|
break;
|
|
}
|
|
case T_Param:
|
|
{
|
|
Param *param = (Param *) first_arg;
|
|
|
|
/*
|
|
* If the Param is a complex type, this could be a
|
|
* projection
|
|
*/
|
|
argtype = param->paramtype;
|
|
argrelid = typeidTypeRelid(argtype);
|
|
if (argrelid &&
|
|
get_attnum(argrelid, funcname) != InvalidAttrNumber)
|
|
{
|
|
fselect = setup_field_select((Node *) param,
|
|
funcname, argrelid);
|
|
return (Node *) fselect;
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Error message when function lookup fails that gives details of the
|
|
* argument types
|
|
*/
|
|
void
|
|
func_error(char *caller, char *funcname, int nargs, Oid *argtypes, char *msg)
|
|
{
|
|
char p[(NAMEDATALEN + 2) * FUNC_MAX_ARGS],
|
|
*ptr;
|
|
int i;
|
|
|
|
ptr = p;
|
|
*ptr = '\0';
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (i)
|
|
{
|
|
*ptr++ = ',';
|
|
*ptr++ = ' ';
|
|
}
|
|
if (argtypes[i] != 0)
|
|
{
|
|
strcpy(ptr, typeidTypeName(argtypes[i]));
|
|
*(ptr + NAMEDATALEN) = '\0';
|
|
}
|
|
else
|
|
strcpy(ptr, "opaque");
|
|
ptr += strlen(ptr);
|
|
}
|
|
|
|
if (caller == NULL)
|
|
{
|
|
elog(ERROR, "Function '%s(%s)' does not exist%s%s",
|
|
funcname, p,
|
|
((msg != NULL) ? "\n\t" : ""), ((msg != NULL) ? msg : ""));
|
|
}
|
|
else
|
|
{
|
|
elog(ERROR, "%s: function '%s(%s)' does not exist%s%s",
|
|
caller, funcname, p,
|
|
((msg != NULL) ? "\n\t" : ""), ((msg != NULL) ? msg : ""));
|
|
}
|
|
}
|