@@ -81,21 +81,18 @@ select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1);
a b
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2 7
select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1)
union (select * from t4 order by a limit 2) limit 3;
select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1) union (select * from t4 order by a limit 2) limit 3;
a b
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2 7
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select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1)
union (select * from t4 where t4.b=(select max(t2.a)*4 from t2) order by a);
select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1) union (select * from t4 where t4.b=(select max(t2.a)*4 from t2) order by a);
a b
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2 7
3 8
4 8
explain select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1)
union (select * from t4 where t4.b=(select max(t2.a)*4 from t2) order by a);
explain select * from t2 where t2.b=(select a from t3 order by 1 desc limit 1) union (select * from t4 where t4.b=(select max(t2.a)*4 from t2) order by a);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 Using where
2 SUBSELECT t3 ALL NULL NULL NULL NULL 3 Using filesort
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@@ -330,19 +327,15 @@ Unknown column 'a' in 'having clause'
SELECT * from t2 where topic IN (SELECT topic FROM t2 GROUP BY date);
mot topic date pseudo
joce 40143 2002-10-22 joce
joce 43506 2002-10-22 joce
SELECT * from t2 where topic IN (SELECT topic FROM t2 GROUP BY date HAVING topic < 4100);
mot topic date pseudo
joce 43506 2002-10-22 joce
SELECT * from t2 where topic IN (SELECT SUM(topic) FROM t1);
mot topic date pseudo
SELECT * from t2 where topic = any (SELECT topic FROM t2 GROUP BY date);
mot topic date pseudo
joce 40143 2002-10-22 joce
joce 43506 2002-10-22 joce
SELECT * from t2 where topic = any (SELECT topic FROM t2 GROUP BY date HAVING topic < 4100);
mot topic date pseudo
joce 43506 2002-10-22 joce
SELECT * from t2 where topic = any (SELECT SUM(topic) FROM t1);
mot topic date pseudo
SELECT * from t2 where topic = all (SELECT topic FROM t2 GROUP BY date);
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@@ -351,6 +344,7 @@ joce 40143 2002-10-22 joce
SELECT * from t2 where topic = all (SELECT topic FROM t2 GROUP BY date HAVING topic < 4100);
mot topic date pseudo
joce 40143 2002-10-22 joce
joce 43506 2002-10-22 joce
SELECT * from t2 where topic = all (SELECT SUM(topic) FROM t2);
mot topic date pseudo
SELECT * from t2 where topic <> any (SELECT SUM(topic) FROM t2);