Index: src/backend/optimizer/prep/prepjointree.c
===================================================================
RCS file: /projects/cvsroot/pgsql-server/src/backend/optimizer/prep/prepjointree.c,v
retrieving revision 1.7
diff -u -r1.7 prepjointree.c
--- src/backend/optimizer/prep/prepjointree.c	2003/03/10 03:53:50	1.7
+++ src/backend/optimizer/prep/prepjointree.c	2003/05/03 07:25:10
@@ -745,10 +745,7 @@
  *
  * We don't use expression_tree_walker here because we don't want to
  * descend through very many kinds of nodes; only the ones we can be sure
- * are strict.  We can descend through the top level of implicit AND'ing,
- * but not through any explicit ANDs (or ORs) below that, since those are not
- * strict constructs.  The List case handles the top-level implicit AND list
- * as well as lists of arguments to strict operators/functions.
+ * are strict.
  */
 static Relids
 find_nonnullable_rels(Node *node, bool top_level)
@@ -791,10 +788,45 @@
 	else if (IsA(node, BoolExpr))
 	{
 		BoolExpr   *expr = (BoolExpr *) node;
+		List       *l;
 
-		/* NOT is strict, others are not */
-		if (expr->boolop == NOT_EXPR)
-			result = find_nonnullable_rels((Node *) expr->args, false);
+		switch (expr->boolop) {
+		 	case AND_EXPR:
+				/* All nonnullable rels from the AND are nonnullable at this
+				 * level.
+				 */
+				foreach(l, expr->args)
+				{
+					result = bms_join(result, find_nonnullable_rels(lfirst(l),
+																	top_level));
+				}
+				break;
+			case OR_EXPR:
+				/* For OR, a rel is nonnullable only if it is nonnullable for
+				 * all of the expressions making up the BoolExpr.
+				 */
+				result = find_nonnullable_rels(lfirst(expr->args),
+											   top_level);
+				foreach(l, lnext(expr->args))
+				{
+					/* If the set is empty, then nothing further will help */
+					if (bms_is_empty(result))
+						break;
+
+					result = bms_int_members(result, find_nonnullable_rels(lfirst(l),
+																		   top_level));
+				}
+				break;
+			case NOT_EXPR:
+				/* The NOT doesn't change the nullability of the rels, except
+				 * for IS NOT NULL, which is handled below
+				 */
+				result = find_nonnullable_rels((Node *) expr->args, false);
+				break;
+			default:
+				elog(ERROR, "find_nonnullable_rels: unknown boolop %d",
+					 expr->boolop);
+		}
 	}
 	else if (IsA(node, RelabelType))
 	{