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95ef6a3448
the parsetree representation. As yet we don't *do* anything with schema names, just drop 'em on the floor; but you can enter schema-compatible command syntax, and there's even a primitive CREATE SCHEMA command. No doc updates yet, except to note that you can now extract a field from a function-returning-row's result with (foo(...)).fieldname.
121 lines
2.5 KiB
C
121 lines
2.5 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) 1996-2001, 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/nodes/nodeFuncs.c,v 1.17 2002/03/21 16:00:40 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include <sys/types.h>
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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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* replace_opid -
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*
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* Given a oper node, resets the opfid field with the
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* procedure OID (regproc id).
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*
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* Returns the modified oper node.
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*
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*/
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Oper *
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replace_opid(Oper *oper)
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{
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oper->opid = get_opcode(oper->opno);
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oper->op_fcache = NULL;
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return oper;
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}
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/*****************************************************************************
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* constant (CONST, PARAM) nodes
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*****************************************************************************/
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#ifdef NOT_USED
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/*
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* non_null -
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* Returns t if the node is a non-null constant, e.g., if the node has a
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* valid `constvalue' field.
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*/
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bool
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non_null(Expr *c)
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{
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if (IsA(c, Const) &&
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!((Const *) c)->constisnull)
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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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#endif
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