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Some simple optimisation

= ANY and <> ALL converted to (NOT) IN to get advantage of IN optimisation
This commit is contained in:
bell@laptop.sanja.is.com.ua
2003-10-08 17:40:54 +03:00
parent 381b680868
commit afac13d033
5 changed files with 69 additions and 18 deletions

View File

@ -1403,6 +1403,16 @@ s1 s1 NOT IN (SELECT s1 FROM t2)
a1 0
a2 0
a3 1
select s1, s1 = ANY (SELECT s1 FROM t2) from t1;
s1 s1 = ANY (SELECT s1 FROM t2)
a1 1
a2 1
a3 0
select s1, s1 <> ALL (SELECT s1 FROM t2) from t1;
s1 s1 <> ALL (SELECT s1 FROM t2)
a1 0
a2 0
a3 1
select s1, s1 NOT IN (SELECT s1 FROM t2 WHERE s1 < 'a2') from t1;
s1 s1 NOT IN (SELECT s1 FROM t2 WHERE s1 < 'a2')
a1 0
@ -1412,6 +1422,14 @@ explain select s1, s1 NOT IN (SELECT s1 FROM t2) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index NULL s1 6 NULL 3 Using index
2 DEPENDENT SUBQUERY t2 index_subquery s1 s1 6 func 2 Using index
explain select s1, s1 = ANY (SELECT s1 FROM t2) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index NULL s1 6 NULL 3 Using index
2 DEPENDENT SUBQUERY t2 index_subquery s1 s1 6 func 2 Using index
explain select s1, s1 <> ALL (SELECT s1 FROM t2) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index NULL s1 6 NULL 3 Using index
2 DEPENDENT SUBQUERY t2 index_subquery s1 s1 6 func 2 Using index
explain select s1, s1 NOT IN (SELECT s1 FROM t2 WHERE s1 < 'a2') from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index NULL s1 6 NULL 3 Using index