rocksdb.group_min_max fails in bb, result length mismatch

rocksdb.group_min_max 'write_committed'  w3 [ fail ]

        Test ended at 2021-06-23 19:53:45

CURRENT_TEST: rocksdb.group_min_max

--- /usr/share/mysql-test/plugin/rocksdb/rocksdb/r/group_min_max.result	2021-06-23 16:52:43.000000000 +0000

+++ /dev/shm/var/3/log/group_min_max.reject	2021-06-23 19:53:45.413086684 +0000

@@ -2346,10 +2346,10 @@

 BB

 EXPLAIN SELECT a FROM t1 WHERE a='AA' GROUP BY a;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

-1	SIMPLE	t1	ref	PRIMARY	PRIMARY	7	const	1000	Using where; Using index

+1	SIMPLE	t1	range	PRIMARY	PRIMARY	7	NULL	501	Using where; Using index for group-by

 EXPLAIN SELECT a FROM t1 WHERE a='BB' GROUP BY a;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

-1	SIMPLE	t1	ref	PRIMARY	PRIMARY	7	const	1000	Using where; Using index

+1	SIMPLE	t1	range	PRIMARY	PRIMARY	7	NULL	501	Using where; Using index for group-by

 SELECT DISTINCT a FROM t1 WHERE a='BB';

 a

 BB

@@ -2777,7 +2777,7 @@

 3	13

 explain extended select sql_buffer_result a, max(b)+1 from t1 where a = 0 group by a;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra

-1	SIMPLE	t1	ref	PRIMARY,index	PRIMARY	4	const	15	6.67	Using index; Using temporary

+1	SIMPLE	t1	range	PRIMARY,index	PRIMARY	4	NULL	1	100.00	Using where; Using index for group-by; Using temporary

 Warnings:

 Note	1003	select sql_buffer_result `test`.`t1`.`a` AS `a`,max(`test`.`t1`.`b`) + 1 AS `max(b)+1` from `test`.`t1` where `test`.`t1`.`a` = 0 group by `test`.`t1`.`a`

 drop table t1;

@@ -3505,7 +3505,7 @@

 test.t1	analyze	status	OK

 EXPLAIN SELECT MAX(c2), c1 FROM t1 WHERE c1 = 4 GROUP BY c1;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

-1	SIMPLE	t1	ref	c1	c1	5	const	28	Using index

+1	SIMPLE	t1	range	c1	c1	5	NULL	6	Using where; Using index for group-by

 FLUSH STATUS;

 SELECT MAX(c2), c1 FROM t1 WHERE c1 = 4 GROUP BY c1;

 MAX(c2)	c1

@@ -3513,9 +3513,9 @@

 SHOW SESSION STATUS LIKE 'Handler_read%';

 Variable_name	Value

 Handler_read_first	0

-Handler_read_key	1

-Handler_read_last	0

-Handler_read_next	20

+Handler_read_key	3

+Handler_read_last	1

+Handler_read_next	0

 Handler_read_prev	0

 Handler_read_retry	0

 Handler_read_rnd	0

mysqltest: Result length mismatch