diff options
Diffstat (limited to 'src/backend/executor/execQual.c')
| -rw-r--r-- | src/backend/executor/execQual.c | 168 |
1 files changed, 166 insertions, 2 deletions
diff --git a/src/backend/executor/execQual.c b/src/backend/executor/execQual.c index cb31c025df2..e7c724c66ed 100644 --- a/src/backend/executor/execQual.c +++ b/src/backend/executor/execQual.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.112 2002/12/01 20:27:32 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.113 2002/12/05 15:50:31 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1766,7 +1766,8 @@ ExecEvalExpr(Node *expression, isNull, isDone); break; case SUBPLAN_EXPR: - retDatum = ExecSubPlan((SubPlan *) expr->oper, + /* XXX temporary hack to find exec state node */ + retDatum = ExecSubPlan(((SubPlan *) expr->oper)->pstate, expr->args, econtext, isNull); break; @@ -1850,6 +1851,169 @@ ExecEvalExprSwitchContext(Node *expression, } +/* + * ExecInitExpr: prepare an expression tree for execution + * + * 'node' is the root of the expression tree to examine + * 'parent' is the PlanState node that owns the expression, + * or NULL if we are preparing an expression that is not associated + * with a plan. (If so, it can't have Aggrefs or SubPlans.) + * + * Soon this will generate an expression state tree paralleling the given + * expression tree. Right now, it just searches the expression tree for + * Aggref and SubPlan nodes. + */ +Node * +ExecInitExpr(Node *node, PlanState *parent) +{ + List *temp; + + if (node == NULL) + return NULL; + switch (nodeTag(node)) + { + case T_Var: + break; + case T_Const: + break; + case T_Param: + break; + case T_Aggref: + if (parent && IsA(parent, AggState)) + { + AggState *aggstate = (AggState *) parent; + int naggs; + + aggstate->aggs = lcons(node, aggstate->aggs); + naggs = ++aggstate->numaggs; + + ExecInitExpr(((Aggref *) node)->target, parent); + + /* + * Complain if the aggregate's argument contains any + * aggregates; nested agg functions are semantically + * nonsensical. (This probably was caught earlier, + * but we defend against it here anyway.) + */ + if (naggs != aggstate->numaggs) + elog(ERROR, "Aggregate function calls may not be nested"); + } + else + elog(ERROR, "ExecInitExpr: Aggref not expected here"); + break; + case T_ArrayRef: + { + ArrayRef *aref = (ArrayRef *) node; + + ExecInitExpr((Node *) aref->refupperindexpr, parent); + ExecInitExpr((Node *) aref->reflowerindexpr, parent); + ExecInitExpr(aref->refexpr, parent); + ExecInitExpr(aref->refassgnexpr, parent); + } + break; + case T_Expr: + { + Expr *expr = (Expr *) node; + + switch (expr->opType) + { + case OP_EXPR: + break; + case FUNC_EXPR: + break; + case OR_EXPR: + break; + case AND_EXPR: + break; + case NOT_EXPR: + break; + case DISTINCT_EXPR: + break; + case SUBPLAN_EXPR: + if (parent) + { + SubLink *sublink = ((SubPlan *) expr->oper)->sublink; + + /* + * Here we just add the SubPlan nodes to + * parent->subPlan. Later they will be expanded + * to SubPlanState nodes. + */ + parent->subPlan = lcons(expr->oper, + parent->subPlan); + + /* Must recurse into oper list too */ + Assert(IsA(sublink, SubLink)); + if (sublink->lefthand) + elog(ERROR, "ExecInitExpr: sublink has not been transformed"); + ExecInitExpr((Node *) sublink->oper, parent); + } + else + elog(ERROR, "ExecInitExpr: SubPlan not expected here"); + break; + default: + elog(ERROR, "ExecInitExpr: unknown expression type %d", + expr->opType); + break; + } + /* for all Expr node types, examine args list */ + ExecInitExpr((Node *) expr->args, parent); + } + break; + case T_FieldSelect: + ExecInitExpr(((FieldSelect *) node)->arg, parent); + break; + case T_RelabelType: + ExecInitExpr(((RelabelType *) node)->arg, parent); + break; + case T_CaseExpr: + { + CaseExpr *caseexpr = (CaseExpr *) node; + + foreach(temp, caseexpr->args) + { + CaseWhen *when = (CaseWhen *) lfirst(temp); + + Assert(IsA(when, CaseWhen)); + ExecInitExpr(when->expr, parent); + ExecInitExpr(when->result, parent); + } + /* caseexpr->arg should be null, but we'll check it anyway */ + ExecInitExpr(caseexpr->arg, parent); + ExecInitExpr(caseexpr->defresult, parent); + } + break; + case T_NullTest: + ExecInitExpr(((NullTest *) node)->arg, parent); + break; + case T_BooleanTest: + ExecInitExpr(((BooleanTest *) node)->arg, parent); + break; + case T_ConstraintTest: + ExecInitExpr(((ConstraintTest *) node)->arg, parent); + ExecInitExpr(((ConstraintTest *) node)->check_expr, parent); + break; + case T_ConstraintTestValue: + break; + case T_List: + foreach(temp, (List *) node) + { + ExecInitExpr((Node *) lfirst(temp), parent); + } + break; + case T_TargetEntry: + ExecInitExpr(((TargetEntry *) node)->expr, parent); + break; + default: + elog(ERROR, "ExecInitExpr: unknown expression type %d", + nodeTag(node)); + break; + } + + return node; +} + + /* ---------------------------------------------------------------- * ExecQual / ExecTargetList / ExecProject * ---------------------------------------------------------------- |