Fixed LP bug #609121

The bug was a result of missing logic to handle the case
when there are 'expensive' predicates that are not evaluated
during constant table optimization. Such is the case for
the IN predicate, which is considered expensive if it is
computed via materialization. In general this bug can be
triggered with any expensive predicate instead of IN.

When FALSE constant predicates are not evaluated during constant
optimization, the execution path changes so that instead of
setting JOIN::zero_result_cause after make_join_select, and
exiting JOIN::exec via the call to return_zero_rows(), execution
ends in JOIN::exec in the branch:
if (join->tables == join->const_tables)
{
  ...
  else if (join->send_row_on_empty_set())
     ...
     rc= join->result->send_data(*columns_list);
}
Unlike return_zero_rows(), this branch didn't evaluate the
having clause of the query.

The patch adds a call to evaluate the HAVING clause of a query even
when all tables are constant, because even for an empty result set
some aggregate functions may produce a NULL value.

mysql-test/r/subselect_mat.result

@@ -1272,3 +1272,28 @@ a	a in (select a from t1)
 1	0
 2	0
 drop table t0, t1;
+#
+# LPBUG#609121: RQG: wrong result on aggregate + NOT IN + HAVING and
+# partial_match_table_scan=on
+#
+create table t1 (c1 int);
+create table t2 (c2 int);
+insert into t1 values (1);
+insert into t2 values (2);
+set @@optimizer_switch='semijoin=off';
+EXPLAIN
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	1	
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+c1_sum
+NULL
+EXPLAIN
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2) HAVING c1_sum;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	1	
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2) HAVING c1_sum;
+c1_sum
+drop table t1, t2;

mysql-test/t/subselect_mat.test

@@ -921,3 +921,25 @@ execute s;
 update t1 set a=123;
 execute s;
 drop table t0, t1;
+
+
+--echo #
+--echo # LPBUG#609121: RQG: wrong result on aggregate + NOT IN + HAVING and
+--echo # partial_match_table_scan=on
+--echo #
+
+create table t1 (c1 int);
+create table t2 (c2 int);
+insert into t1 values (1);
+insert into t2 values (2);
+
+set @@optimizer_switch='semijoin=off';
+
+EXPLAIN
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+EXPLAIN
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2) HAVING c1_sum;
+SELECT SUM(c1) c1_sum FROM t1 WHERE c1 IN (SELECT c2 FROM t2) HAVING c1_sum;
+
+drop table t1, t2;

sql/sql_select.h

@@ -1722,7 +1722,8 @@ class JOIN :public Sql_alloc
   bool send_row_on_empty_set()
   {
     return (do_send_rows && tmp_table_param.sum_func_count != 0 &&
-	    !group_list && having_value != Item::COND_FALSE);
+	    !group_list && having_value != Item::COND_FALSE &&
+            (!having || having->val_int()));
   }
   bool change_result(select_result *result);
   bool is_top_level_join() const