that the inputs to a given operator can be recursively simplified to
constants, it was evaluating the operator using the op's *original*
(unsimplified) arg list, so that any subexpressions had to be evaluated
again. A constant subexpression at depth N got evaluated N times.
Probably not very important in practical situations, but it made us look
real slow in MySQL's 'crashme' test...
- * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.60 2000/02/20 21:32:06 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.61 2000/03/12 19:32:06 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
* duplication of code and ensure we get the same result
* as the executor would get.
*
* duplication of code and ensure we get the same result
* as the executor would get.
*
- * The only setup needed here is the replace_opid()
- * that we already did for the OP_EXPR case.
- *
+ * Build a new Expr node containing the already-simplified
+ * arguments. The only other setup needed here is the
+ * replace_opid() that we already did for the OP_EXPR case.
+ */
+ newexpr = makeNode(Expr);
+ newexpr->typeOid = expr->typeOid;
+ newexpr->opType = expr->opType;
+ newexpr->oper = expr->oper;
+ newexpr->args = args;
+ /*
* It is OK to pass econtext = NULL because none of the
* ExecEvalExpr() code used in this situation will use
* econtext. That might seem fortuitous, but it's not
* so unreasonable --- a constant expression does not
* depend on context, by definition, n'est ce pas?
*/
* It is OK to pass econtext = NULL because none of the
* ExecEvalExpr() code used in this situation will use
* econtext. That might seem fortuitous, but it's not
* so unreasonable --- a constant expression does not
* depend on context, by definition, n'est ce pas?
*/
- const_val = ExecEvalExpr((Node *) expr, NULL,
+ const_val = ExecEvalExpr((Node *) newexpr, NULL,
&const_is_null, &isDone);
Assert(isDone); /* if this isn't set, we blew it... */
&const_is_null, &isDone);
Assert(isDone); /* if this isn't set, we blew it... */
/*
* Make the constant result node.
*/
/*
* Make the constant result node.
*/