diff options
Diffstat (limited to 'src/backend/optimizer/util/clauses.c')
-rw-r--r-- | src/backend/optimizer/util/clauses.c | 109 |
1 files changed, 58 insertions, 51 deletions
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index f653640ee8c..4dabbf50dac 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.169 2004/04/02 23:14:08 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.170 2004/05/10 22:44:45 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -41,10 +41,6 @@ #include "utils/syscache.h" -/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */ -#define MAKEBOOLCONST(val,isnull) \ - ((Node *) makeConst(BOOLOID, 1, (Datum) (val), (isnull), true)) - typedef struct { int nargs; @@ -281,7 +277,7 @@ Expr * make_ands_explicit(List *andclauses) { if (andclauses == NIL) - return (Expr *) MAKEBOOLCONST(true, false); + return (Expr *) makeBoolConst(true, false); else if (lnext(andclauses) == NIL) return (Expr *) lfirst(andclauses); else @@ -484,6 +480,8 @@ expression_returns_set_walker(Node *node, void *context) return false; if (IsA(node, ArrayExpr)) return false; + if (IsA(node, RowExpr)) + return false; if (IsA(node, CoalesceExpr)) return false; if (IsA(node, NullIfExpr)) @@ -778,6 +776,8 @@ contain_nonstrict_functions_walker(Node *node, void *context) if (IsA(node, CaseWhen)) return true; /* NB: ArrayExpr might someday be nonstrict */ + if (IsA(node, RowExpr)) + return true; if (IsA(node, CoalesceExpr)) return true; if (IsA(node, NullIfExpr)) @@ -1030,6 +1030,8 @@ set_coercionform_dontcare_walker(Node *node, void *context) ((FuncExpr *) node)->funcformat = COERCE_DONTCARE; if (IsA(node, RelabelType)) ((RelabelType *) node)->relabelformat = COERCE_DONTCARE; + if (IsA(node, RowExpr)) + ((RowExpr *) node)->row_format = COERCE_DONTCARE; if (IsA(node, CoerceToDomain)) ((CoerceToDomain *) node)->coercionformat = COERCE_DONTCARE; return expression_tree_walker(node, set_coercionform_dontcare_walker, @@ -1197,11 +1199,11 @@ eval_const_expressions_mutator(Node *node, List *active_fns) { /* all nulls? then not distinct */ if (all_null_input) - return MAKEBOOLCONST(false, false); + return makeBoolConst(false, false); /* one null? then distinct */ if (has_null_input) - return MAKEBOOLCONST(true, false); + return makeBoolConst(true, false); /* otherwise try to evaluate the '=' operator */ /* (NOT okay to try to inline it, though!) */ @@ -1272,12 +1274,12 @@ eval_const_expressions_mutator(Node *node, List *active_fns) newargs = simplify_or_arguments(args, &haveNull, &forceTrue); if (forceTrue) - return MAKEBOOLCONST(true, false); + return makeBoolConst(true, false); if (haveNull) - newargs = lappend(newargs, MAKEBOOLCONST(false, true)); + newargs = lappend(newargs, makeBoolConst(false, true)); /* If all the inputs are FALSE, result is FALSE */ if (newargs == NIL) - return MAKEBOOLCONST(false, false); + return makeBoolConst(false, false); /* If only one nonconst-or-NULL input, it's the result */ if (lnext(newargs) == NIL) return (Node *) lfirst(newargs); @@ -1293,12 +1295,12 @@ eval_const_expressions_mutator(Node *node, List *active_fns) newargs = simplify_and_arguments(args, &haveNull, &forceFalse); if (forceFalse) - return MAKEBOOLCONST(false, false); + return makeBoolConst(false, false); if (haveNull) - newargs = lappend(newargs, MAKEBOOLCONST(false, true)); + newargs = lappend(newargs, makeBoolConst(false, true)); /* If all the inputs are TRUE, result is TRUE */ if (newargs == NIL) - return MAKEBOOLCONST(true, false); + return makeBoolConst(true, false); /* If only one nonconst-or-NULL input, it's the result */ if (lnext(newargs) == NIL) return (Node *) lfirst(newargs); @@ -1313,9 +1315,9 @@ eval_const_expressions_mutator(Node *node, List *active_fns) /* NOT NULL => NULL */ if (const_input->constisnull) - return MAKEBOOLCONST(false, true); + return makeBoolConst(false, true); /* otherwise pretty easy */ - return MAKEBOOLCONST(!DatumGetBool(const_input->constvalue), + return makeBoolConst(!DatumGetBool(const_input->constvalue), false); } else if (not_clause((Node *) lfirst(args))) @@ -1387,7 +1389,6 @@ eval_const_expressions_mutator(Node *node, List *active_fns) } if (IsA(node, CaseExpr)) { - /*---------- * CASE expressions can be simplified if there are constant * condition clauses: @@ -1546,22 +1547,38 @@ eval_const_expressions_mutator(Node *node, List *active_fns) * We can optimize field selection from a whole-row Var into a * simple Var. (This case won't be generated directly by the * parser, because ParseComplexProjection short-circuits it. But - * it can arise while simplifying functions.) If the argument - * isn't a whole-row Var, just fall through to do generic - * processing. + * it can arise while simplifying functions.) Also, we can + * optimize field selection from a RowExpr construct. */ FieldSelect *fselect = (FieldSelect *) node; - Var *argvar = (Var *) fselect->arg; + FieldSelect *newfselect; + Node *arg; - if (argvar && IsA(argvar, Var) && - argvar->varattno == InvalidAttrNumber) + arg = eval_const_expressions_mutator((Node *) fselect->arg, + active_fns); + if (arg && IsA(arg, Var) && + ((Var *) arg)->varattno == InvalidAttrNumber) { - return (Node *) makeVar(argvar->varno, + return (Node *) makeVar(((Var *) arg)->varno, fselect->fieldnum, fselect->resulttype, fselect->resulttypmod, - argvar->varlevelsup); + ((Var *) arg)->varlevelsup); } + if (arg && IsA(arg, RowExpr)) + { + RowExpr *rowexpr = (RowExpr *) arg; + + if (fselect->fieldnum > 0 && + fselect->fieldnum <= length(rowexpr->args)) + return (Node *) nth(fselect->fieldnum - 1, rowexpr->args); + } + newfselect = makeNode(FieldSelect); + newfselect->arg = (Expr *) arg; + newfselect->fieldnum = fselect->fieldnum; + newfselect->resulttype = fselect->resulttype; + newfselect->resulttypmod = fselect->resulttypmod; + return (Node *) newfselect; } /* @@ -1759,7 +1776,6 @@ evaluate_function(Oid funcid, Oid result_type, List *args, bool has_null_input = false; List *arg; FuncExpr *newexpr; - char result_typtype; /* * Can't simplify if it returns a set. @@ -1797,15 +1813,6 @@ evaluate_function(Oid funcid, Oid result_type, List *args, return NULL; /* - * Can't simplify functions returning composite types (mainly because - * datumCopy() doesn't cope; FIXME someday when we have a saner - * representation for whole-tuple results). - */ - result_typtype = get_typtype(funcform->prorettype); - if (result_typtype == 'c') - return NULL; - - /* * OK, looks like we can simplify this operator/function. * * Build a new FuncExpr node containing the already-simplified arguments. @@ -1850,7 +1857,6 @@ inline_function(Oid funcid, Oid result_type, List *args, HeapTuple func_tuple, List *active_fns) { Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple); - char result_typtype; bool polymorphic = false; Oid argtypes[FUNC_MAX_ARGS]; char *src; @@ -1877,21 +1883,6 @@ inline_function(Oid funcid, Oid result_type, List *args, funcform->pronargs != length(args)) return NULL; - /* - * Forget it if declared return type is not base, domain, or - * polymorphic - */ - result_typtype = get_typtype(funcform->prorettype); - if (result_typtype != 'b' && - result_typtype != 'd') - { - if (funcform->prorettype == ANYARRAYOID || - funcform->prorettype == ANYELEMENTOID) - polymorphic = true; - else - return NULL; - } - /* Check for recursive function, and give up trying to expand if so */ if (oidMember(funcid, active_fns)) return NULL; @@ -1912,6 +1903,10 @@ inline_function(Oid funcid, Oid result_type, List *args, } } + if (funcform->prorettype == ANYARRAYOID || + funcform->prorettype == ANYELEMENTOID) + polymorphic = true; + /* * Setup error traceback support for ereport(). This is so that we * can finger the function that bad information came from. @@ -2483,6 +2478,8 @@ expression_tree_walker(Node *node, break; case T_ArrayExpr: return walker(((ArrayExpr *) node)->elements, context); + case T_RowExpr: + return walker(((RowExpr *) node)->args, context); case T_CoalesceExpr: return walker(((CoalesceExpr *) node)->args, context); case T_NullIfExpr: @@ -2889,6 +2886,16 @@ expression_tree_mutator(Node *node, return (Node *) newnode; } break; + case T_RowExpr: + { + RowExpr *rowexpr = (RowExpr *) node; + RowExpr *newnode; + + FLATCOPY(newnode, rowexpr, RowExpr); + MUTATE(newnode->args, rowexpr->args, List *); + return (Node *) newnode; + } + break; case T_CoalesceExpr: { CoalesceExpr *coalesceexpr = (CoalesceExpr *) node; |