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execution state trees, and ExecEvalExpr takes an expression state tree not an expression plan tree. The plan tree is now read-only as far as the executor is concerned. Next step is to begin actually exploiting this property.
92 lines
2.0 KiB
C
92 lines
2.0 KiB
C
/*-------------------------------------------------------------------------
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*
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* nodeFuncs.c
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* All node routines more complicated than simple access/modification
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*
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* Portions Copyright (c) 1996-2002, 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/nodes/nodeFuncs.c,v 1.21 2002/12/13 19:45:56 tgl 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 "nodes/nodeFuncs.h"
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#include "utils/lsyscache.h"
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static bool var_is_inner(Var *var);
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/*
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* single_node -
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* Returns t if node corresponds to a single-noded expression
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*/
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bool
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single_node(Node *node)
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{
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if (IsA(node, Const) ||
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IsA(node, Var) ||
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IsA(node, Param))
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return true;
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else
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return false;
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}
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/*****************************************************************************
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* VAR nodes
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*****************************************************************************/
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/*
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* var_is_outer
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* var_is_inner
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* var_is_mat
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* var_is_rel
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*
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* Returns t iff the var node corresponds to (respectively):
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* the outer relation in a join
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* the inner relation of a join
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* a materialized relation
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* a base relation (i.e., not an attribute reference, a variable from
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* some lower join level, or a sort result)
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* var node is an array reference
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*
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*/
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bool
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var_is_outer(Var *var)
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{
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return (bool) (var->varno == OUTER);
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}
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static bool
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var_is_inner(Var *var)
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{
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return (bool) (var->varno == INNER);
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}
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bool
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var_is_rel(Var *var)
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{
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return (bool)
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!(var_is_inner(var) || var_is_outer(var));
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}
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/*****************************************************************************
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* OPER nodes
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*****************************************************************************/
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/*
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* set_opfuncid -
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*
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* Set the opfuncid (procedure OID) in an OpExpr node,
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* if it hasn't been set already.
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*/
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void
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set_opfuncid(OpExpr *opexpr)
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{
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if (opexpr->opfuncid == InvalidOid)
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opexpr->opfuncid = get_opcode(opexpr->opno);
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}
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