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Optimisation if simple IN subselect with primary index

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(SCRUM) (part of WL#818)


mysql-test/r/subselect.result:
  test of new optimisation
mysql-test/t/subselect.test:
  test of new optimisation
sql/item_subselect.cc:
  new engine for simple IN with primary index
sql/item_subselect.h:
  new engine for simple IN with primary index
sql/sql_lex.h:
  fixed typo
sql/sql_select.cc:
  engine changing
  report_error can't be static, because it used in new engine
sql/sql_select.h:
  new JT_ type (just for information in EXPLAIN statement)
  report_error can't be static, because it used in new engine
This commit is contained in:
unknown
2003-07-07 18:40:19 +03:00
parent 2cd6d8ec6b
commit 923dba86b1
7 changed files with 177 additions and 10 deletions
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10
mysql-test/r/subselect.result
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@@ -1226,7 +1226,15 @@ a
explain select * from t2 where t2.a in (select a from t1);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 index NULL PRIMARY 4 NULL 4 Using where; Using index
2 DEPENDENT SUBQUERY t1 eq_ref PRIMARY PRIMARY 4 func 1 Using where; Using index
2 DEPENDENT SUBQUERY t1 simple_in PRIMARY PRIMARY 4 func 1 Using index
select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
a
2
4
explain select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 index NULL PRIMARY 4 NULL 4 Using where; Using index
2 DEPENDENT SUBQUERY t1 simple_in PRIMARY PRIMARY 4 func 1 Using index; Using where
select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
a
2