DROP TABLE IF EXISTS t1;
CREATE TABLE t1
(
key1 INT NOT NULL,
key2 INT NOT NULL,
key3 INT NOT NULL,
key4 INT NOT NULL,
key5 INT,
key6 INT,
key7 INT NOT NULL,
key8 INT NOT NULL,
INDEX i1(key1),
INDEX i2(key2),
INDEX i3(key3),
INDEX i4(key4),
INDEX i5(key5),
INDEX i6(key6)
);
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
DROP TABLE IF EXISTS t2;
CREATE TABLE t2 LIKE t1;
INSERT INTO t2 SELECT * FROM t1;
ANALYZE TABLE t2;
Table	Op	Msg_type	Msg_text
test.t2	analyze	status	Table is already up to date
EXPLAIN UPDATE t1 SET key6=7 WHERE key1=80 OR key4=49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using union(i1,i4); Using where
SELECT COUNT(*), SUM(key6) FROM t1 WHERE key1=80 OR key4=49;
COUNT(*)	SUM(key6)
3	129
UPDATE t1 SET key6=7 WHERE key1=80 OR key4=49;
SELECT COUNT(*), SUM(key6) FROM t1 WHERE key1=80 OR key4=49;
COUNT(*)	SUM(key6)
3	21
EXPLAIN UPDATE t1 SET key1=18 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i2,i3,i5,i6	i3,i5,i2	4,5,4	NULL	#	Using union(intersect(i3,i5),i2); Using where
SELECT COUNT(*), SUM(key1) FROM t1 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
COUNT(*)	SUM(key1)
1	80
UPDATE t1 SET key1=18 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
SELECT COUNT(*), SUM(key1) FROM t1 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
COUNT(*)	SUM(key1)
1	18
EXPLAIN UPDATE t1 SET key3=18 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2,i4,i5,i6	i4,i5	4,5	NULL	#	Using union(i4,i5); Using where
SELECT COUNT(*), SUM(key3) FROM t1 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
COUNT(*)	SUM(key3)
10	287
UPDATE t1 SET key3=18 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
SELECT COUNT(*), SUM(key3) FROM t1 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
COUNT(*)	SUM(key3)
10	180
EXPLAIN UPDATE t1 SET key8=64 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i2,i3	i2,i3	4,4	NULL	#	Using union(i2,i3); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
COUNT(*)	SUM(key8)
3	1185
UPDATE t1 SET key8=64 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
COUNT(*)	SUM(key8)
3	192
EXPLAIN UPDATE t1 SET key8=18 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2,i3,i4,i5,i6	i5,i6	5,5	NULL	#	Using sort_union(i5,i6); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
COUNT(*)	SUM(key8)
1	1
UPDATE t1 SET key8=18 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
SELECT COUNT(*), SUM(key8) FROM t1 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
COUNT(*)	SUM(key8)
1	18
EXPLAIN UPDATE t1 SET key3=32 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2	i1,i2	4,4	NULL	#	Using sort_union(i1,i2); Using where
SELECT COUNT(*), SUM(key3) FROM t1 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
COUNT(*)	SUM(key3)
39	1168
UPDATE t1 SET key3=32 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
SELECT COUNT(*), SUM(key3) FROM t1 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
COUNT(*)	SUM(key3)
39	1248
EXPLAIN UPDATE t1 SET key7=25 WHERE key1 IN (15,70) OR key2 IN (15,70);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2	i1,i2	4,4	NULL	#	Using sort_union(i1,i2); Using where
SELECT COUNT(*), SUM(key7) FROM t1 WHERE key1 IN (15,70) OR key2 IN (15,70);
COUNT(*)	SUM(key7)
2	85
UPDATE t1 SET key7=25 WHERE key1 IN (15,70) OR key2 IN (15,70);
SELECT COUNT(*), SUM(key7) FROM t1 WHERE key1 IN (15,70) OR key2 IN (15,70);
COUNT(*)	SUM(key7)
2	50
EXPLAIN UPDATE t1 SET key1=10 WHERE key5<5 OR key8<10 ORDER BY key1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	#	Using where; Using filesort
SELECT COUNT(*), SUM(key1) FROM t1 WHERE key5<5 OR key8<10 ORDER BY key1;
COUNT(*)	SUM(key1)
11	56
UPDATE t1 SET key1=10 WHERE key5<5 OR key8<10 ORDER BY key1;
SELECT COUNT(*), SUM(key1) FROM t1 WHERE key5<5 OR key8<10 ORDER BY key1;
COUNT(*)	SUM(key1)
11	110
EXPLAIN UPDATE t1 left join t2 ON (t2.key1=t2.key1) SET t1.key4=15 WHERE t1.key5=40 OR t1.key4=15;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i4,i5	i5,i4	5,4	NULL	#	Using union(i5,i4); Using where
1	SIMPLE	t2	index	NULL	i1	4	NULL	#	Using where; Using index; Using join buffer (Block Nested Loop)
SELECT COUNT(*), SUM(key4) FROM t1;
COUNT(*)	SUM(key4)
2057	2098421
UPDATE t1 left join t2 ON (t2.key1=t2.key1) SET t1.key4=15 WHERE t1.key5=40 OR t1.key4=15;
SELECT COUNT(*), SUM(key4) FROM t1;
COUNT(*)	SUM(key4)
2057	2098396
EXPLAIN UPDATE t2 SET key7=7 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	index_merge	i3,i4	i3,i4	4,4	NULL	#	Using union(i3,i4); Using where
2	SUBQUERY	t1	index_merge	i1,i5	i1,i5	4,5	NULL	#	Using union(i1,i5); Using where
SELECT COUNT(*), SUM(key7) FROM t2 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
COUNT(*)	SUM(key7)
0	NULL
UPDATE t2 SET key7=7 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
SELECT COUNT(*), SUM(key7) FROM t2 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
COUNT(*)	SUM(key7)
0	NULL
EXPLAIN UPDATE t2 SET key2=2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using union(i1,i4); Using where
3	SUBQUERY	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where
2	SUBQUERY	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where
SELECT COUNT(*), SUM(key2) FROM t2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
COUNT(*)	SUM(key2)
1	25
UPDATE t2 SET key2=2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
SELECT COUNT(*), SUM(key2) FROM t2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
COUNT(*)	SUM(key2)
1	2
EXPLAIN UPDATE t2 SET key3=20 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	#	NULL
2	SUBQUERY	t1	index_merge	i4,i6	i6,i4	5,4	NULL	#	Using sort_union(i6,i4); Using where
SELECT COUNT(*), SUM(key3) FROM t2 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
COUNT(*)	SUM(key3)
2057	2098421
UPDATE t2 SET key3=20 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
SELECT COUNT(*), SUM(key3) FROM t2 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
COUNT(*)	SUM(key3)
2057	41140
EXPLAIN UPDATE t1 SET key8=50 WHERE key5=80 OR key6=49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i5,i6	i5,i6	5,5	NULL	#	Using union(i5,i6); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key5=80 OR key6=49;
COUNT(*)	SUM(key8)
1	64
UPDATE t1 SET key8=50 WHERE key5=80 OR key6=49;
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key5=80 OR key6=49;
COUNT(*)	SUM(key8)
1	50
DROP TABLE IF EXISTS t1;
CREATE TABLE t1
(
key1 INT NOT NULL,
key2 INT NOT NULL,
key3 INT NOT NULL,
key4 INT NOT NULL,
key5 INT,
key6 INT,
key7 INT NOT NULL,
key8 INT NOT NULL,
INDEX i1(key1,key2),
INDEX i2(key2,key1),
INDEX i3(key3,key4),
INDEX i4(key4,key3),
INDEX i5(key5,key6),
INDEX i6(key6,key5),
INDEX i7(key7,key8),
INDEX i8(key8,key7)
);
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
DROP TABLE IF EXISTS t2;
CREATE TABLE t2 LIKE t1;
INSERT INTO t2 SELECT * FROM t1;
ANALYZE TABLE t2;
Table	Op	Msg_type	Msg_text
test.t2	analyze	status	Table is already up to date
EXPLAIN UPDATE t1 SET key6=7 WHERE key1=80 OR key4=49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where
SELECT COUNT(*), SUM(key6) FROM t1 WHERE key1=80 OR key4=49;
COUNT(*)	SUM(key6)
3	129
UPDATE t1 SET key6=7 WHERE key1=80 OR key4=49;
SELECT COUNT(*), SUM(key6) FROM t1 WHERE key1=80 OR key4=49;
COUNT(*)	SUM(key6)
3	21
EXPLAIN UPDATE t1 SET key1=18 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i2,i3,i5,i6	i3,i2	4,4	NULL	#	Using sort_union(i3,i2); Using where; Using temporary
SELECT COUNT(*), SUM(key1) FROM t1 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
COUNT(*)	SUM(key1)
1	80
UPDATE t1 SET key1=18 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
SELECT COUNT(*), SUM(key1) FROM t1 WHERE (key3=80 AND key5 IS NULL) OR (key2=49 AND key6 IS NULL);
COUNT(*)	SUM(key1)
1	18
EXPLAIN UPDATE t1 SET key3=18 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2,i4,i5,i6	i4,i5	4,5	NULL	#	Using sort_union(i4,i5); Using where; Using temporary
SELECT COUNT(*), SUM(key3) FROM t1 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
COUNT(*)	SUM(key3)
10	287
UPDATE t1 SET key3=18 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
SELECT COUNT(*), SUM(key3) FROM t1 WHERE (key4=42 AND key6 IS NOT NULL) OR (key1>4 AND key5 IS NULL) AND key2<>50;
COUNT(*)	SUM(key3)
10	180
EXPLAIN UPDATE t1 SET key8=64 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i2,i3	i2,i3	4,4	NULL	#	Using sort_union(i2,i3); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
COUNT(*)	SUM(key8)
3	1185
UPDATE t1 SET key8=64 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key2=80 OR key3=1025 OR key4 <=> NULL;
COUNT(*)	SUM(key8)
3	192
EXPLAIN UPDATE t1 SET key8=18 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2,i3,i4,i5,i6	i5,i6	5,5	NULL	#	Using sort_union(i5,i6); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
COUNT(*)	SUM(key8)
1	1
UPDATE t1 SET key8=18 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
SELECT COUNT(*), SUM(key8) FROM t1 WHERE (key1 < 3 OR key2 < 2) AND (key3 < 3 OR key4 < 3) AND (key5 < 2 OR key6 < 2);
COUNT(*)	SUM(key8)
1	18
EXPLAIN UPDATE t1 SET key3=32 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2	i1,i2	4,4	NULL	#	Using sort_union(i1,i2); Using where
SELECT COUNT(*), SUM(key3) FROM t1 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
COUNT(*)	SUM(key3)
39	1168
UPDATE t1 SET key3=32 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
SELECT COUNT(*), SUM(key3) FROM t1 WHERE key1 between 25 AND 40 OR key2 between 15 AND 49;
COUNT(*)	SUM(key3)
39	1248
EXPLAIN UPDATE t1 SET key7=25 WHERE key1 IN (15,70) OR key2 IN (15,70);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i1,i2	i1,i2	4,4	NULL	#	Using sort_union(i1,i2); Using where
SELECT COUNT(*), SUM(key7) FROM t1 WHERE key1 IN (15,70) OR key2 IN (15,70);
COUNT(*)	SUM(key7)
2	85
UPDATE t1 SET key7=25 WHERE key1 IN (15,70) OR key2 IN (15,70);
SELECT COUNT(*), SUM(key7) FROM t1 WHERE key1 IN (15,70) OR key2 IN (15,70);
COUNT(*)	SUM(key7)
2	50
EXPLAIN UPDATE t1 SET key1=10 WHERE key5<5 OR key8<10 ORDER BY key1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i5,i8	i5,i8	5,4	NULL	#	Using sort_union(i5,i8); Using where; Using filesort
SELECT COUNT(*), SUM(key1) FROM t1 WHERE key5<5 OR key8<10 ORDER BY key1;
COUNT(*)	SUM(key1)
11	56
UPDATE t1 SET key1=10 WHERE key5<5 OR key8<10 ORDER BY key1;
SELECT COUNT(*), SUM(key1) FROM t1 WHERE key5<5 OR key8<10 ORDER BY key1;
COUNT(*)	SUM(key1)
11	110
EXPLAIN UPDATE t1 left join t2 ON (t2.key1=t2.key1) SET t1.key4=15 WHERE t1.key5=40 OR t1.key4=15;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i4,i5	i5,i4	5,4	NULL	#	Using sort_union(i5,i4); Using where
1	SIMPLE	t2	index	NULL	i1	8	NULL	#	Using where; Using index; Using join buffer (Block Nested Loop)
SELECT COUNT(*), SUM(key4) FROM t1;
COUNT(*)	SUM(key4)
2057	2098421
UPDATE t1 left join t2 ON (t2.key1=t2.key1) SET t1.key4=15 WHERE t1.key5=40 OR t1.key4=15;
SELECT COUNT(*), SUM(key4) FROM t1;
COUNT(*)	SUM(key4)
2057	2098396
EXPLAIN UPDATE t2 SET key7=7 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	index_merge	i3,i4	i3,i4	4,4	NULL	#	Using sort_union(i3,i4); Using where
2	SUBQUERY	t1	index_merge	i1,i5	i1,i5	4,5	NULL	#	Using sort_union(i1,i5); Using where
SELECT COUNT(*), SUM(key7) FROM t2 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
COUNT(*)	SUM(key7)
0	NULL
UPDATE t2 SET key7=7 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
SELECT COUNT(*), SUM(key7) FROM t2 WHERE (key3=28 OR key4=10)  AND key6 < ANY (SELECT key6 FROM t1 WHERE key1=10 OR key5=3);
COUNT(*)	SUM(key7)
0	NULL
EXPLAIN UPDATE t2 SET key2=2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where; Using temporary
3	SUBQUERY	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where
2	SUBQUERY	t1	index_merge	i1,i4	i1,i4	4,4	NULL	#	Using sort_union(i1,i4); Using where
SELECT COUNT(*), SUM(key2) FROM t2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
COUNT(*)	SUM(key2)
1	25
UPDATE t2 SET key2=2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
SELECT COUNT(*), SUM(key2) FROM t2 WHERE key1=25 OR key4=40 AND (key4 < SOME (SELECT key4 FROM t1 WHERE key1<5 OR key4<8) OR key1 < ANY (SELECT key1 FROM t1 WHERE key1<5 OR key4<7));
COUNT(*)	SUM(key2)
1	2
EXPLAIN UPDATE t2 SET key3=20 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	#	NULL
2	SUBQUERY	t1	index_merge	i4,i6	i6,i4	5,4	NULL	#	Using sort_union(i6,i4); Using where
SELECT COUNT(*), SUM(key3) FROM t2 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
COUNT(*)	SUM(key3)
2057	2098421
UPDATE t2 SET key3=20 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
SELECT COUNT(*), SUM(key3) FROM t2 WHERE EXISTS (SELECT * FROM t1 WHERE key6<3 OR key4<10);
COUNT(*)	SUM(key3)
2057	41140
EXPLAIN UPDATE t1 SET key8=50 WHERE key5=80 OR key6=49;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index_merge	i5,i6	i5,i6	5,5	NULL	#	Using sort_union(i5,i6); Using where
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key5=80 OR key6=49;
COUNT(*)	SUM(key8)
1	64
UPDATE t1 SET key8=50 WHERE key5=80 OR key6=49;
SELECT COUNT(*), SUM(key8) FROM t1 WHERE key5=80 OR key6=49;
COUNT(*)	SUM(key8)
1	50
DROP TABLE t1;
DROP TABLE t2;
