bugfix: join a=b where cast(a as type_of_b) can produce NULL

optimizer implicitly assumed that if `a` in `a=b` is not NULL, then it's safe to convert `a` to the type of `b` and search the result in the index(b). which is not always the case, as converting a non-null value to a different type might produce NULL. And searching for NULL in the index might find NULL there, so NULL will be equal to NULL, making `a=b` behave as if it was `a<=>b`

bugfix: join a=b where cast(a as type_of_b) can produce NULL
optimizer implicitly assumed that if `a` in `a=b` is not NULL, then it's safe to convert `a` to the type of `b` and search the result in the index(b). which is not always the case, as converting a non-null value to a different type might produce NULL. And searching for NULL in the index might find NULL there, so NULL will be equal to NULL, making `a=b` behave as if it was `a<=>b`
1570c6e3 · Sergei Golubchik · ef84f813 · 1570c6e3 · 1570c6e3 · 1570c6e3
Commit 1570c6e3 authored Jul 05, 2023 by Sergei Golubchik
4 changed files
--- a/mysql-test/main/subselect_cache.result
+++ b/mysql-test/main/subselect_cache.result
@@ -1698,7 +1698,7 @@ Subquery_cache_miss	18
 show status like '%Handler_read%';
 Variable_name	Value
 Handler_read_first	0
-Handler_read_key	32
+Handler_read_key	29
 Handler_read_last	0
 Handler_read_next	0
 Handler_read_prev	0
@@ -1763,7 +1763,7 @@ Subquery_cache_miss	10
 show status like '%Handler_read%';
 Variable_name	Value
 Handler_read_first	0
-Handler_read_key	13
+Handler_read_key	12
 Handler_read_last	0
 Handler_read_next	0
 Handler_read_prev	0

--- a/plugin/type_uuid/mysql-test/type_uuid/order.result
+++ b/plugin/type_uuid/mysql-test/type_uuid/order.result
@@ -288,7 +288,11 @@ t2	CREATE TABLE `t2` (
  `b` int(11) NOT NULL,
  KEY `a` (`a`)
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
-select * from t1, t2 where t1.a=t2.a;
+explain select * from t1 left join t2 on (t1.a=t2.a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	64	
+1	SIMPLE	t2	ref	a	a	17	test.t1.a	1	Using where
+select * from t1 left join t2 on (t1.a=t2.a);
 a	b	a	b
 11223344-5566-0777-0888-99aabbccddee	0	11223344-5566-0777-0888-99aabbccddee	0
 11223344-5566-0777-8888-99aabbccddee	1	11223344-5566-0777-8888-99aabbccddee	1
@@ -346,6 +350,345 @@ a	b	a	b
 11223344-5566-f777-8888-99aabbccddee	61	11223344-5566-f777-8888-99aabbccddee	61
 11223344-5566-f777-c888-99aabbccddee	62	11223344-5566-f777-c888-99aabbccddee	62
 11223344-5566-f777-e888-99aabbccddee	63	11223344-5566-f777-e888-99aabbccddee	63
+NULL	32	NULL	NULL
+NULL	36	NULL	NULL
+NULL	40	NULL	NULL
+NULL	44	NULL	NULL
+NULL	48	NULL	NULL
+NULL	52	NULL	NULL
+NULL	56	NULL	NULL
+NULL	60	NULL	NULL
+explain select * from t1 left join t2 on (t1.a<=>t2.a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	64	
+1	SIMPLE	t2	ref	a	a	17	test.t1.a	1	Using where
+select * from t1 left join t2 on (t1.a<=>t2.a);
+a	b	a	b
+11223344-5566-0777-0888-99aabbccddee	0	11223344-5566-0777-0888-99aabbccddee	0
+11223344-5566-0777-8888-99aabbccddee	1	11223344-5566-0777-8888-99aabbccddee	1
+11223344-5566-0777-c888-99aabbccddee	2	11223344-5566-0777-c888-99aabbccddee	2
+11223344-5566-0777-e888-99aabbccddee	3	11223344-5566-0777-e888-99aabbccddee	3
+11223344-5566-1777-0888-99aabbccddee	4	11223344-5566-1777-0888-99aabbccddee	4
+11223344-5566-1777-8888-99aabbccddee	5	11223344-5566-1777-8888-99aabbccddee	5
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+11223344-5566-a777-e888-99aabbccddee	43	11223344-5566-a777-e888-99aabbccddee	43
+11223344-5566-b777-8888-99aabbccddee	45	11223344-5566-b777-8888-99aabbccddee	45
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+11223344-5566-b777-e888-99aabbccddee	47	11223344-5566-b777-e888-99aabbccddee	47
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+11223344-5566-c777-c888-99aabbccddee	50	11223344-5566-c777-c888-99aabbccddee	50
+11223344-5566-c777-e888-99aabbccddee	51	11223344-5566-c777-e888-99aabbccddee	51
+11223344-5566-d777-8888-99aabbccddee	53	11223344-5566-d777-8888-99aabbccddee	53
+11223344-5566-d777-c888-99aabbccddee	54	11223344-5566-d777-c888-99aabbccddee	54
+11223344-5566-d777-e888-99aabbccddee	55	11223344-5566-d777-e888-99aabbccddee	55
+11223344-5566-e777-8888-99aabbccddee	57	11223344-5566-e777-8888-99aabbccddee	57
+11223344-5566-e777-c888-99aabbccddee	58	11223344-5566-e777-c888-99aabbccddee	58
+11223344-5566-e777-e888-99aabbccddee	59	11223344-5566-e777-e888-99aabbccddee	59
+11223344-5566-f777-8888-99aabbccddee	61	11223344-5566-f777-8888-99aabbccddee	61
+11223344-5566-f777-c888-99aabbccddee	62	11223344-5566-f777-c888-99aabbccddee	62
+11223344-5566-f777-e888-99aabbccddee	63	11223344-5566-f777-e888-99aabbccddee	63
+NULL	32	NULL	NULL
+NULL	36	NULL	NULL
+NULL	40	NULL	NULL
+NULL	44	NULL	NULL
+NULL	48	NULL	NULL
+NULL	52	NULL	NULL
+NULL	56	NULL	NULL
+NULL	60	NULL	NULL
+explain select * from t2 left join t1 on (t1.a=t2.a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	64	
+1	SIMPLE	t1	ref	a	a	17	test.t2.a	1	Using where
+select * from t2 left join t1 on (t1.a=t2.a);
+a	b	a	b
+11223344-5566-0777-0888-99aabbccddee	0	11223344-5566-0777-0888-99aabbccddee	0
+11223344-5566-0777-8888-99aabbccddee	1	11223344-5566-0777-8888-99aabbccddee	1
+11223344-5566-0777-c888-99aabbccddee	2	11223344-5566-0777-c888-99aabbccddee	2
+11223344-5566-0777-e888-99aabbccddee	3	11223344-5566-0777-e888-99aabbccddee	3
+11223344-5566-1777-0888-99aabbccddee	4	11223344-5566-1777-0888-99aabbccddee	4
+11223344-5566-1777-8888-99aabbccddee	5	11223344-5566-1777-8888-99aabbccddee	5
+11223344-5566-1777-c888-99aabbccddee	6	11223344-5566-1777-c888-99aabbccddee	6
+11223344-5566-1777-e888-99aabbccddee	7	11223344-5566-1777-e888-99aabbccddee	7
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+11223344-5566-4777-8888-99aabbccddee	17	11223344-5566-4777-8888-99aabbccddee	17
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+11223344-5566-5777-e888-99aabbccddee	23	11223344-5566-5777-e888-99aabbccddee	23
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+11223344-5566-6777-8888-99aabbccddee	25	11223344-5566-6777-8888-99aabbccddee	25
+11223344-5566-6777-c888-99aabbccddee	26	11223344-5566-6777-c888-99aabbccddee	26
+11223344-5566-6777-e888-99aabbccddee	27	11223344-5566-6777-e888-99aabbccddee	27
+11223344-5566-7777-0888-99aabbccddee	28	11223344-5566-7777-0888-99aabbccddee	28
+11223344-5566-7777-8888-99aabbccddee	29	11223344-5566-7777-8888-99aabbccddee	29
+11223344-5566-7777-c888-99aabbccddee	30	11223344-5566-7777-c888-99aabbccddee	30
+11223344-5566-7777-e888-99aabbccddee	31	11223344-5566-7777-e888-99aabbccddee	31
+11223344-5566-8777-0888-99aabbccddee	32	NULL	NULL
+11223344-5566-8777-8888-99aabbccddee	33	11223344-5566-8777-8888-99aabbccddee	33
+11223344-5566-8777-c888-99aabbccddee	34	11223344-5566-8777-c888-99aabbccddee	34
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+11223344-5566-9777-0888-99aabbccddee	36	NULL	NULL
+11223344-5566-9777-8888-99aabbccddee	37	11223344-5566-9777-8888-99aabbccddee	37
+11223344-5566-9777-c888-99aabbccddee	38	11223344-5566-9777-c888-99aabbccddee	38
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+11223344-5566-a777-0888-99aabbccddee	40	NULL	NULL
+11223344-5566-a777-8888-99aabbccddee	41	11223344-5566-a777-8888-99aabbccddee	41
+11223344-5566-a777-c888-99aabbccddee	42	11223344-5566-a777-c888-99aabbccddee	42
+11223344-5566-a777-e888-99aabbccddee	43	11223344-5566-a777-e888-99aabbccddee	43
+11223344-5566-b777-0888-99aabbccddee	44	NULL	NULL
+11223344-5566-b777-8888-99aabbccddee	45	11223344-5566-b777-8888-99aabbccddee	45
+11223344-5566-b777-c888-99aabbccddee	46	11223344-5566-b777-c888-99aabbccddee	46
+11223344-5566-b777-e888-99aabbccddee	47	11223344-5566-b777-e888-99aabbccddee	47
+11223344-5566-c777-0888-99aabbccddee	48	NULL	NULL
+11223344-5566-c777-8888-99aabbccddee	49	11223344-5566-c777-8888-99aabbccddee	49
+11223344-5566-c777-c888-99aabbccddee	50	11223344-5566-c777-c888-99aabbccddee	50
+11223344-5566-c777-e888-99aabbccddee	51	11223344-5566-c777-e888-99aabbccddee	51
+11223344-5566-d777-0888-99aabbccddee	52	NULL	NULL
+11223344-5566-d777-8888-99aabbccddee	53	11223344-5566-d777-8888-99aabbccddee	53
+11223344-5566-d777-c888-99aabbccddee	54	11223344-5566-d777-c888-99aabbccddee	54
+11223344-5566-d777-e888-99aabbccddee	55	11223344-5566-d777-e888-99aabbccddee	55
+11223344-5566-e777-0888-99aabbccddee	56	NULL	NULL
+11223344-5566-e777-8888-99aabbccddee	57	11223344-5566-e777-8888-99aabbccddee	57
+11223344-5566-e777-c888-99aabbccddee	58	11223344-5566-e777-c888-99aabbccddee	58
+11223344-5566-e777-e888-99aabbccddee	59	11223344-5566-e777-e888-99aabbccddee	59
+11223344-5566-f777-0888-99aabbccddee	60	NULL	NULL
+11223344-5566-f777-8888-99aabbccddee	61	11223344-5566-f777-8888-99aabbccddee	61
+11223344-5566-f777-c888-99aabbccddee	62	11223344-5566-f777-c888-99aabbccddee	62
+11223344-5566-f777-e888-99aabbccddee	63	11223344-5566-f777-e888-99aabbccddee	63
+explain select * from t2 left join t1 on (t1.a<=>t2.a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	64	
+1	SIMPLE	t1	ref	a	a	17	test.t2.a	1	Using where
+select * from t2 left join t1 on (t1.a<=>t2.a);
+a	b	a	b
+11223344-5566-0777-0888-99aabbccddee	0	11223344-5566-0777-0888-99aabbccddee	0
+11223344-5566-0777-8888-99aabbccddee	1	11223344-5566-0777-8888-99aabbccddee	1
+11223344-5566-0777-c888-99aabbccddee	2	11223344-5566-0777-c888-99aabbccddee	2
+11223344-5566-0777-e888-99aabbccddee	3	11223344-5566-0777-e888-99aabbccddee	3
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+11223344-5566-5777-c888-99aabbccddee	22	11223344-5566-5777-c888-99aabbccddee	22
+11223344-5566-5777-e888-99aabbccddee	23	11223344-5566-5777-e888-99aabbccddee	23
+11223344-5566-6777-0888-99aabbccddee	24	11223344-5566-6777-0888-99aabbccddee	24
+11223344-5566-6777-8888-99aabbccddee	25	11223344-5566-6777-8888-99aabbccddee	25
+11223344-5566-6777-c888-99aabbccddee	26	11223344-5566-6777-c888-99aabbccddee	26
+11223344-5566-6777-e888-99aabbccddee	27	11223344-5566-6777-e888-99aabbccddee	27
+11223344-5566-7777-0888-99aabbccddee	28	11223344-5566-7777-0888-99aabbccddee	28
+11223344-5566-7777-8888-99aabbccddee	29	11223344-5566-7777-8888-99aabbccddee	29
+11223344-5566-7777-c888-99aabbccddee	30	11223344-5566-7777-c888-99aabbccddee	30
+11223344-5566-7777-e888-99aabbccddee	31	11223344-5566-7777-e888-99aabbccddee	31
+11223344-5566-8777-0888-99aabbccddee	32	NULL	32
+11223344-5566-8777-0888-99aabbccddee	32	NULL	36
+11223344-5566-8777-0888-99aabbccddee	32	NULL	40
+11223344-5566-8777-0888-99aabbccddee	32	NULL	44
+11223344-5566-8777-0888-99aabbccddee	32	NULL	48
+11223344-5566-8777-0888-99aabbccddee	32	NULL	52
+11223344-5566-8777-0888-99aabbccddee	32	NULL	56
+11223344-5566-8777-0888-99aabbccddee	32	NULL	60
+11223344-5566-8777-8888-99aabbccddee	33	11223344-5566-8777-8888-99aabbccddee	33
+11223344-5566-8777-c888-99aabbccddee	34	11223344-5566-8777-c888-99aabbccddee	34
+11223344-5566-8777-e888-99aabbccddee	35	11223344-5566-8777-e888-99aabbccddee	35
+11223344-5566-9777-0888-99aabbccddee	36	NULL	32
+11223344-5566-9777-0888-99aabbccddee	36	NULL	36
+11223344-5566-9777-0888-99aabbccddee	36	NULL	40
+11223344-5566-9777-0888-99aabbccddee	36	NULL	44
+11223344-5566-9777-0888-99aabbccddee	36	NULL	48
+11223344-5566-9777-0888-99aabbccddee	36	NULL	52
+11223344-5566-9777-0888-99aabbccddee	36	NULL	56
+11223344-5566-9777-0888-99aabbccddee	36	NULL	60
+11223344-5566-9777-8888-99aabbccddee	37	11223344-5566-9777-8888-99aabbccddee	37
+11223344-5566-9777-c888-99aabbccddee	38	11223344-5566-9777-c888-99aabbccddee	38
+11223344-5566-9777-e888-99aabbccddee	39	11223344-5566-9777-e888-99aabbccddee	39
+11223344-5566-a777-0888-99aabbccddee	40	NULL	32
+11223344-5566-a777-0888-99aabbccddee	40	NULL	36
+11223344-5566-a777-0888-99aabbccddee	40	NULL	40
+11223344-5566-a777-0888-99aabbccddee	40	NULL	44
+11223344-5566-a777-0888-99aabbccddee	40	NULL	48
+11223344-5566-a777-0888-99aabbccddee	40	NULL	52
+11223344-5566-a777-0888-99aabbccddee	40	NULL	56
+11223344-5566-a777-0888-99aabbccddee	40	NULL	60
+11223344-5566-a777-8888-99aabbccddee	41	11223344-5566-a777-8888-99aabbccddee	41
+11223344-5566-a777-c888-99aabbccddee	42	11223344-5566-a777-c888-99aabbccddee	42
+11223344-5566-a777-e888-99aabbccddee	43	11223344-5566-a777-e888-99aabbccddee	43
+11223344-5566-b777-0888-99aabbccddee	44	NULL	32
+11223344-5566-b777-0888-99aabbccddee	44	NULL	36
+11223344-5566-b777-0888-99aabbccddee	44	NULL	40
+11223344-5566-b777-0888-99aabbccddee	44	NULL	44
+11223344-5566-b777-0888-99aabbccddee	44	NULL	48
+11223344-5566-b777-0888-99aabbccddee	44	NULL	52
+11223344-5566-b777-0888-99aabbccddee	44	NULL	56
+11223344-5566-b777-0888-99aabbccddee	44	NULL	60
+11223344-5566-b777-8888-99aabbccddee	45	11223344-5566-b777-8888-99aabbccddee	45
+11223344-5566-b777-c888-99aabbccddee	46	11223344-5566-b777-c888-99aabbccddee	46
+11223344-5566-b777-e888-99aabbccddee	47	11223344-5566-b777-e888-99aabbccddee	47
+11223344-5566-c777-0888-99aabbccddee	48	NULL	32
+11223344-5566-c777-0888-99aabbccddee	48	NULL	36
+11223344-5566-c777-0888-99aabbccddee	48	NULL	40
+11223344-5566-c777-0888-99aabbccddee	48	NULL	44
+11223344-5566-c777-0888-99aabbccddee	48	NULL	48
+11223344-5566-c777-0888-99aabbccddee	48	NULL	52
+11223344-5566-c777-0888-99aabbccddee	48	NULL	56
+11223344-5566-c777-0888-99aabbccddee	48	NULL	60
+11223344-5566-c777-8888-99aabbccddee	49	11223344-5566-c777-8888-99aabbccddee	49
+11223344-5566-c777-c888-99aabbccddee	50	11223344-5566-c777-c888-99aabbccddee	50
+11223344-5566-c777-e888-99aabbccddee	51	11223344-5566-c777-e888-99aabbccddee	51
+11223344-5566-d777-0888-99aabbccddee	52	NULL	32
+11223344-5566-d777-0888-99aabbccddee	52	NULL	36
+11223344-5566-d777-0888-99aabbccddee	52	NULL	40
+11223344-5566-d777-0888-99aabbccddee	52	NULL	44
+11223344-5566-d777-0888-99aabbccddee	52	NULL	48
+11223344-5566-d777-0888-99aabbccddee	52	NULL	52
+11223344-5566-d777-0888-99aabbccddee	52	NULL	56
+11223344-5566-d777-0888-99aabbccddee	52	NULL	60
+11223344-5566-d777-8888-99aabbccddee	53	11223344-5566-d777-8888-99aabbccddee	53
+11223344-5566-d777-c888-99aabbccddee	54	11223344-5566-d777-c888-99aabbccddee	54
+11223344-5566-d777-e888-99aabbccddee	55	11223344-5566-d777-e888-99aabbccddee	55
+11223344-5566-e777-0888-99aabbccddee	56	NULL	32
+11223344-5566-e777-0888-99aabbccddee	56	NULL	36
+11223344-5566-e777-0888-99aabbccddee	56	NULL	40
+11223344-5566-e777-0888-99aabbccddee	56	NULL	44
+11223344-5566-e777-0888-99aabbccddee	56	NULL	48
+11223344-5566-e777-0888-99aabbccddee	56	NULL	52
+11223344-5566-e777-0888-99aabbccddee	56	NULL	56
+11223344-5566-e777-0888-99aabbccddee	56	NULL	60
+11223344-5566-e777-8888-99aabbccddee	57	11223344-5566-e777-8888-99aabbccddee	57
+11223344-5566-e777-c888-99aabbccddee	58	11223344-5566-e777-c888-99aabbccddee	58
+11223344-5566-e777-e888-99aabbccddee	59	11223344-5566-e777-e888-99aabbccddee	59
+11223344-5566-f777-0888-99aabbccddee	60	NULL	32
+11223344-5566-f777-0888-99aabbccddee	60	NULL	36
+11223344-5566-f777-0888-99aabbccddee	60	NULL	40
+11223344-5566-f777-0888-99aabbccddee	60	NULL	44
+11223344-5566-f777-0888-99aabbccddee	60	NULL	48
+11223344-5566-f777-0888-99aabbccddee	60	NULL	52
+11223344-5566-f777-0888-99aabbccddee	60	NULL	56
+11223344-5566-f777-0888-99aabbccddee	60	NULL	60
+11223344-5566-f777-8888-99aabbccddee	61	11223344-5566-f777-8888-99aabbccddee	61
+11223344-5566-f777-c888-99aabbccddee	62	11223344-5566-f777-c888-99aabbccddee	62
+11223344-5566-f777-e888-99aabbccddee	63	11223344-5566-f777-e888-99aabbccddee	63
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-8777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-9777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-a777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-b777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-c777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-d777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-e777-0888-99aabbccddee'
+Warning	1292	Incorrect uuid value: '11223344-5566-f777-0888-99aabbccddee'
+Warnings:
 select * from t1 union select * from t2;
 a	b
 11223344-5566-0777-0888-99aabbccddee	0

--- a/plugin/type_uuid/mysql-test/type_uuid/order.test
+++ b/plugin/type_uuid/mysql-test/type_uuid/order.test
@@ -16,7 +16,21 @@ select * from t2;
 select * from t2 order by a;
 show create table t2;

-select * from t1, t2 where t1.a=t2.a;
+explain select * from t1 left join t2 on (t1.a=t2.a);
+--sorted_result
+select * from t1 left join t2 on (t1.a=t2.a);
+
+explain select * from t1 left join t2 on (t1.a<=>t2.a);
+--sorted_result
+select * from t1 left join t2 on (t1.a<=>t2.a);
+
+explain select * from t2 left join t1 on (t1.a=t2.a);
+--sorted_result
+select * from t2 left join t1 on (t1.a=t2.a);
+
+explain select * from t2 left join t1 on (t1.a<=>t2.a);
+--sorted_result
+select * from t2 left join t1 on (t1.a<=>t2.a);

 --sorted_result
 select * from t1 union select * from t2;

--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -25562,7 +25562,8 @@ cp_buffer_from_ref(THD *thd, TABLE *table, TABLE_REF *ref)
  thd->count_cuted_fields= CHECK_FIELD_IGNORE;
  for (store_key **copy=ref->key_copy ; *copy ; copy++)
  {
-    if ((*copy)->copy(thd) & 1)
+    if ((*copy)->copy(thd) & 1 ||
+        (ref->null_rejecting && (*copy)->null_key))
    {
      result= 1;
      break;