Merge pull request #392 from citusdata/bugfix/#258-spurious-notice-message-with-any

Fix spurious NOTICE messages with ANY/ALL

src/backend/distributed/planner/multi_physical_planner.c

@@ -2896,8 +2896,25 @@ HashableClauseMutator(Node *originalNode, Var *partitionColumn)
 	}
 	else if (IsA(originalNode, ScalarArrayOpExpr))
 	{
-		ereport(NOTICE, (errmsg("cannot use shard pruning with ANY (array expression)"),
+		ScalarArrayOpExpr *arrayOperatorExpression = (ScalarArrayOpExpr *) originalNode;
-						 errhint("Consider rewriting the expression with OR clauses.")));
+		Node *leftOpExpression = linitial(arrayOperatorExpression->args);
+		Node *strippedLeftOpExpression = strip_implicit_coercions(leftOpExpression);
+		char *operatorName = get_opname(arrayOperatorExpression->opno);
+		int equalsCompare = strncmp(operatorName, EQUAL_OPERATOR_STRING, NAMEDATALEN);
+		bool usingEqualityOperator = (equalsCompare == 0);
+
+		/*
+		 * Citus cannot prune hash-distributed shards with ANY/ALL. We show a NOTICE
+		 * if the expression is ANY/ALL performed on the partition column with equality.
+		 */
+		if (usingEqualityOperator && strippedLeftOpExpression != NULL &&
+			equal(strippedLeftOpExpression, partitionColumn))
+		{
+			ereport(NOTICE, (errmsg("cannot use shard pruning with "
+									"ANY/ALL (array expression)"),
+							 errhint("Consider rewriting the expression with "
+									 "OR/AND clauses.")));
+		}
 	}
 
 	/*

src/test/regress/expected/multi_hash_pruning.out

@@ -175,11 +175,30 @@ DEBUG:  predicate pruning for shardId 111
  explain statements for distributed queries are currently unsupported
 (1 row)
 
--- Check that we don't support pruning for ANY (array expression)
+-- Check that we don't support pruning for ANY (array expression) and give
+-- a notice message when used with the partition column
+EXPLAIN SELECT count(*) FROM orders_hash_partitioned
+	WHERE o_orderkey = ANY ('{1,2,3}');
+NOTICE:  cannot use shard pruning with ANY/ALL (array expression)
+HINT:  Consider rewriting the expression with OR/AND clauses.
+                              QUERY PLAN                              
+----------------------------------------------------------------------
+ explain statements for distributed queries are currently unsupported
+(1 row)
+
+-- Check that we don't show the message if the operator is not
+-- equality operator
+EXPLAIN SELECT count(*) FROM orders_hash_partitioned
+	WHERE o_orderkey < ALL ('{1,2,3}');
+                              QUERY PLAN                              
+----------------------------------------------------------------------
+ explain statements for distributed queries are currently unsupported
+(1 row)
+
+-- Check that we don't give a spurious hint message when non-partition 
+-- columns are used with ANY/IN/ALL
 EXPLAIN SELECT count(*) FROM orders_hash_partitioned
 	WHERE o_orderkey = 1 OR o_totalprice IN (2, 5);
-NOTICE:  cannot use shard pruning with ANY (array expression)
-HINT:  Consider rewriting the expression with OR clauses.
                               QUERY PLAN                              
 ----------------------------------------------------------------------
  explain statements for distributed queries are currently unsupported

src/test/regress/sql/multi_hash_pruning.sql

@@ -91,8 +91,18 @@ EXPLAIN SELECT count(*) FROM
 
 EXPLAIN SELECT count(*) FROM orders_hash_partitioned WHERE o_orderkey = abs(-1);
 
--- Check that we don't support pruning for ANY (array expression)
+-- Check that we don't support pruning for ANY (array expression) and give
+-- a notice message when used with the partition column
+EXPLAIN SELECT count(*) FROM orders_hash_partitioned
+	WHERE o_orderkey = ANY ('{1,2,3}');
 
+-- Check that we don't show the message if the operator is not
+-- equality operator
+EXPLAIN SELECT count(*) FROM orders_hash_partitioned
+	WHERE o_orderkey < ALL ('{1,2,3}');
+
+-- Check that we don't give a spurious hint message when non-partition 
+-- columns are used with ANY/IN/ALL
 EXPLAIN SELECT count(*) FROM orders_hash_partitioned
 	WHERE o_orderkey = 1 OR o_totalprice IN (2, 5);