Support expressions of the form 'scalar op ANY (array)' and

'scalar op ALL (array)', where the operator is applied between the
lefthand scalar and each element of the array.  The operator must
yield boolean; the result of the construct is the OR or AND of the
per-element results, respectively.

Original coding by Joe Conway, after an idea of Peter's.  Rewritten
by Tom to keep the implementation strictly separate from subqueries.

src/include/nodes/primnodes.h

@@ -10,7 +10,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: primnodes.h,v 1.85 2003/06/25 21:30:33 momjian Exp $
+ * $Id: primnodes.h,v 1.86 2003/06/29 00:33:44 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -334,6 +334,25 @@ typedef struct OpExpr
  */
 typedef OpExpr DistinctExpr;
 
+/*
+ * ScalarArrayOpExpr - expression node for "scalar op ANY/ALL (array)"
+ *
+ * The operator must yield boolean.  It is applied to the left operand
+ * and each element of the righthand array, and the results are combined
+ * with OR or AND (for ANY or ALL respectively).  The node representation
+ * is almost the same as for the underlying operator, but we need a useOr
+ * flag to remember whether it's ANY or ALL, and we don't have to store
+ * the result type because it must be boolean.
+ */
+typedef struct ScalarArrayOpExpr
+{
+	Expr		xpr;
+	Oid			opno;			/* PG_OPERATOR OID of the operator */
+	Oid			opfuncid;		/* PG_PROC OID of underlying function */
+	bool		useOr;			/* true for ANY, false for ALL */
+	List	   *args;			/* the scalar and array operands */
+} ScalarArrayOpExpr;
+
 /*
  * BoolExpr - expression node for the basic Boolean operators AND, OR, NOT
  *