1 files changed, 115 insertions, 0 deletions
diff --git a/mysql-test/main/group_min_max.test b/mysql-test/main/group_min_max.test
index 506323599cb..3c5c1b5bb9b 100644
--- a/mysql-test/main/group_min_max.test
+++ b/mysql-test/main/group_min_max.test
@@ -5,6 +5,7 @@
 
 --source include/no_valgrind_without_big.inc
 --source include/default_optimizer_switch.inc
+--source include/have_innodb.inc
 
 #
 # TODO:
@@ -1688,3 +1689,117 @@ drop table t1;
 --echo #
 --echo # End of 10.1 tests
 --echo #
+
+--echo #
+--echo # MDEV-6768 Wrong result with agregate with join with no resultset
+--echo #
+
+create table t1
+(
+	PARENT_ID int(10) unsigned NOT NULL AUTO_INCREMENT,
+	PARENT_FIELD VARCHAR(10),
+	PRIMARY KEY (PARENT_ID)
+) engine=innodb;
+
+create table t2
+(
+	CHILD_ID INT NOT NULL AUTO_INCREMENT,
+	PARENT_ID INT NOT NULL,
+	CHILD_FIELD varchar(10),
+	PRIMARY KEY (CHILD_ID)
+)engine=innodb;
+
+INSERT INTO t1 (PARENT_FIELD)
+SELECT 'AAAA';
+
+INSERT INTO t2 (PARENT_ID, CHILD_FIELD)
+SELECT 1, 'BBBB';
+
+explain select
+ t1.PARENT_ID,
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+select
+ t1.PARENT_ID,
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+select
+ 1,
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+select
+ IFNULL(t1.PARENT_ID,1),
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+
+--echo # Check that things works with MyISAM (which has different explain)
+
+alter table t1 engine=myisam;
+alter table t2 engine=myisam;
+
+explain select
+ t1.PARENT_ID,
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+select
+ t1.PARENT_ID,
+ min(CHILD_FIELD)
+ from t1 straight_join t2
+ where t1.PARENT_ID = 1
+ and t1.PARENT_ID = t2.PARENT_ID
+ and t2.CHILD_FIELD = "ZZZZ";
+
+drop table t1,t2;
+
+--echo # Check that things works if sub queries are re-executed
+
+create table t1 (a int primary key, b int);
+create table t2 (a int primary key, b int);
+create table t3 (a int primary key, b int);
+
+insert into t1 values (1,1),(2,2),(3,3);
+insert into t2 values (1,1),(2,2),(3,3);
+insert into t3 values (1,1),(3,3);
+
+explain
+select *,
+   (select
+        CONCAT('t2:',       IFNULL(t2.a,      't2a-null'), ';',
+               'min_t3_b:', IFNULL(min(t3.b), 't3b-null'))
+    from t2,t3
+    where t2.a=1 and t1.b = t3.a) as s1
+from t1;
+
+select *,
+   (select
+        CONCAT('t2:',       IFNULL(t2.a,      't2a-null'), ';',
+               'min_t3_b:', IFNULL(min(t3.b), 't3b-null'))
+    from t2,t3
+    where t2.a=1 and t1.b = t3.a) as s1
+from t1;
+
+drop table t1,t2,t3;
+
+--echo #
+--echo # End of 10.4 tests
+--echo #