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author | Igor Babaev <igor@askmonty.org> | 2017-05-04 22:45:32 -0700 |
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committer | Igor Babaev <igor@askmonty.org> | 2017-05-04 22:45:32 -0700 |
commit | 15f9931f6d2b0eb4006fdc42072c2905fd67c1aa (patch) | |
tree | fff72f8e5466e551753d589b54243a48c13541e9 | |
parent | 14fca28ea44dabf62e75e2aa9a90d71bd7be45c0 (diff) | |
download | mariadb-git-15f9931f6d2b0eb4006fdc42072c2905fd67c1aa.tar.gz |
Fixed the bug mdev-12673.
This patch corrects the fix for the bug mdev-10693.
It is critical for the function get_best_combination() not to call
create_ref_for_key() for constant tables.
This bug could manifest itself only in multi-table subqueries where
one of the tables is accessed by a constant primary key.
-rw-r--r-- | mysql-test/r/subselect_mat_cost_bugs.result | 42 | ||||
-rw-r--r-- | mysql-test/t/subselect_mat_cost_bugs.test | 39 | ||||
-rw-r--r-- | sql/sql_select.cc | 12 |
3 files changed, 88 insertions, 5 deletions
diff --git a/mysql-test/r/subselect_mat_cost_bugs.result b/mysql-test/r/subselect_mat_cost_bugs.result index 24640154c59..9bfd5bd67b5 100644 --- a/mysql-test/r/subselect_mat_cost_bugs.result +++ b/mysql-test/r/subselect_mat_cost_bugs.result @@ -400,3 +400,45 @@ id select_type table type possible_keys key key_len ref rows Extra select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2); c1 c2 drop table t1, t2; +# +# MDEV-12673: cost-based choice between materialization and in-to-exists +# +CREATE TABLE t1 ( +pk1 int, a1 varchar(3), b1 varchar(3), PRIMARY KEY (pk1), KEY(a1), KEY(b1) +) ENGINE=MyISAM; +INSERT INTO t1 VALUES (1,'foo','bar'),(2,'bar','foo'); +CREATE TABLE t2 (pk2 INT PRIMARY KEY, a2 VARCHAR(3), KEY(a2)) ENGINE=MyISAM; +INSERT INTO t2 VALUES (1,'abc'),(2,'xyz'),(3,'foo'); +SELECT 'qux' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); +'qux' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ) +0 +SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); +'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ) +1 +EXPLAIN +SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used +2 SUBQUERY t2 const PRIMARY,a2 PRIMARY 4 const 1 +2 SUBQUERY t1 ref a1,b1 b1 6 const 1 Using where +DROP TABLE t1,t2; +CREATE TABLE t1 (i1 INT) ENGINE=MyISAM; +INSERT INTO t1 VALUES (1); +CREATE TABLE t2 (i2 int, c2 varchar(3), KEY(i2,c2)) ENGINE=MyISAM; +INSERT INTO t2 VALUES (1,'abc'),(2,'foo'); +CREATE TABLE t3 (pk3 int PRIMARY KEY, c3 varchar(3)) ENGINE=MyISAM; +INSERT INTO t3 VALUES (1,'foo'),(2,'bar'); +SELECT * FROM t1 WHERE i1 NOT IN ( +SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1 +); +i1 +1 +EXPLAIN +SELECT * FROM t1 WHERE i1 NOT IN ( +SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1 +); +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY t1 system NULL NULL NULL NULL 1 +2 DEPENDENT SUBQUERY t3 const PRIMARY PRIMARY 4 const 1 +2 DEPENDENT SUBQUERY t2 index NULL i2 11 NULL 2 Using where; Using index +DROP TABLE t1,t2,t3; diff --git a/mysql-test/t/subselect_mat_cost_bugs.test b/mysql-test/t/subselect_mat_cost_bugs.test index 8205e94b203..316ac707bef 100644 --- a/mysql-test/t/subselect_mat_cost_bugs.test +++ b/mysql-test/t/subselect_mat_cost_bugs.test @@ -424,3 +424,42 @@ explain select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2); select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2); drop table t1, t2; + +--echo # +--echo # MDEV-12673: cost-based choice between materialization and in-to-exists +--echo # + +CREATE TABLE t1 ( + pk1 int, a1 varchar(3), b1 varchar(3), PRIMARY KEY (pk1), KEY(a1), KEY(b1) +) ENGINE=MyISAM; +INSERT INTO t1 VALUES (1,'foo','bar'),(2,'bar','foo'); + +CREATE TABLE t2 (pk2 INT PRIMARY KEY, a2 VARCHAR(3), KEY(a2)) ENGINE=MyISAM; +INSERT INTO t2 VALUES (1,'abc'),(2,'xyz'),(3,'foo'); + +SELECT 'qux' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); +SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); +EXPLAIN +SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 ); + +DROP TABLE t1,t2; + +CREATE TABLE t1 (i1 INT) ENGINE=MyISAM; +INSERT INTO t1 VALUES (1); + +CREATE TABLE t2 (i2 int, c2 varchar(3), KEY(i2,c2)) ENGINE=MyISAM; +INSERT INTO t2 VALUES (1,'abc'),(2,'foo'); + +CREATE TABLE t3 (pk3 int PRIMARY KEY, c3 varchar(3)) ENGINE=MyISAM; +INSERT INTO t3 VALUES (1,'foo'),(2,'bar'); + +SELECT * FROM t1 WHERE i1 NOT IN ( + SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1 +); + +EXPLAIN +SELECT * FROM t1 WHERE i1 NOT IN ( + SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1 +); + +DROP TABLE t1,t2,t3; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index c5f2a83fc01..09e6ece7807 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -7844,12 +7844,14 @@ get_best_combination(JOIN *join) { if (j->bush_children) j= j->bush_children->start; - + used_tables|= j->table->map; - if ((keyuse= join->best_positions[tablenr].key) && - create_ref_for_key(join, j, keyuse, TRUE, used_tables)) - DBUG_RETURN(TRUE); // Something went wrong - + if (j->type != JT_CONST && j->type != JT_SYSTEM) + { + if ((keyuse= join->best_positions[tablenr].key) && + create_ref_for_key(join, j, keyuse, TRUE, used_tables)) + DBUG_RETURN(TRUE); // Something went wrong + } if (j->last_leaf_in_bush) j= j->bush_root_tab; } |