mirror of
https://github.com/MariaDB/server.git
synced 2025-01-18 04:53:01 +01:00
369a5f1cdc
The problem from a user's perspective: user creates table A, and then tries to CREATE TABLE a SELECT from A - and this causes a deadlock error, a hang, or fails with a debug assert, but only if the storage engine is InnoDB. The origin of the problem: InnoDB uses case-insensitive collation (system_charset_info) when looking up the internal table share, thus returning the same share for 'a' and 'A'. Cause of the user-visible behavior: since the same share is returned to SQL locking subsystem, it assumes that the same table is first locked (within the same session) for WRITE, and then for READ, and returns a deadlock error. However, the code is wrong in not properly cleaning up upon an error, leaving external locks in place, which leads to assertion failures and hangs. Fix that has been implemented: the SQL layer should properly propagate the deadlock error, cleaning up and freeing all resources. Further work towards a more complete solution: InnoDB should not use case insensitive collation for table share hash if table names on disk honor the case. mysql-test/r/innodb-deadlock.result: Bug#25164 test case result mysql-test/t/innodb-deadlock.test: Bug#25164 test case. The CREATE TABLE may fail depending on the character set of the system and filesystem, but it should never hang. sql/lock.cc: Unlock the storage engine "external" table level locks, if the MySQL thr_lock locking subsystem detects a deadlock error.
107 lines
1.8 KiB
Text
107 lines
1.8 KiB
Text
drop table if exists t1,t2;
|
|
create table t1 (id integer, x integer) engine=INNODB;
|
|
insert into t1 values(0, 0);
|
|
set autocommit=0;
|
|
SELECT * from t1 where id = 0 FOR UPDATE;
|
|
id x
|
|
0 0
|
|
set autocommit=0;
|
|
update t1 set x=2 where id = 0;
|
|
update t1 set x=1 where id = 0;
|
|
select * from t1;
|
|
id x
|
|
0 1
|
|
commit;
|
|
commit;
|
|
select * from t1;
|
|
id x
|
|
0 2
|
|
commit;
|
|
drop table t1;
|
|
create table t1 (id integer, x integer) engine=INNODB;
|
|
create table t2 (b integer, a integer) engine=INNODB;
|
|
insert into t1 values(0, 0), (300, 300);
|
|
insert into t2 values(0, 10), (1, 20), (2, 30);
|
|
commit;
|
|
set autocommit=0;
|
|
select * from t2;
|
|
b a
|
|
0 10
|
|
1 20
|
|
2 30
|
|
update t2 set a=100 where b=(SELECT x from t1 where id = b FOR UPDATE);
|
|
select * from t2;
|
|
b a
|
|
0 100
|
|
1 20
|
|
2 30
|
|
select * from t1;
|
|
id x
|
|
0 0
|
|
300 300
|
|
set autocommit=0;
|
|
update t1 set x=2 where id = 0;
|
|
update t1 set x=1 where id = 0;
|
|
select * from t1;
|
|
id x
|
|
0 1
|
|
300 300
|
|
commit;
|
|
commit;
|
|
select * from t1;
|
|
id x
|
|
0 2
|
|
300 300
|
|
commit;
|
|
drop table t1, t2;
|
|
create table t1 (id integer, x integer) engine=INNODB;
|
|
create table t2 (b integer, a integer) engine=INNODB;
|
|
insert into t1 values(0, 0), (300, 300);
|
|
insert into t2 values(0, 0), (1, 20), (2, 30);
|
|
commit;
|
|
select a,b from t2 UNION SELECT id, x from t1 FOR UPDATE;
|
|
a b
|
|
0 0
|
|
20 1
|
|
30 2
|
|
300 300
|
|
select * from t2;
|
|
b a
|
|
0 0
|
|
1 20
|
|
2 30
|
|
select * from t1;
|
|
id x
|
|
0 0
|
|
300 300
|
|
update t2 set a=2 where b = 0;
|
|
select * from t2;
|
|
b a
|
|
0 2
|
|
1 20
|
|
2 30
|
|
update t1 set x=2 where id = 0;
|
|
update t1 set x=1 where id = 0;
|
|
select * from t1;
|
|
id x
|
|
0 1
|
|
300 300
|
|
commit;
|
|
commit;
|
|
select * from t1;
|
|
id x
|
|
0 2
|
|
300 300
|
|
commit;
|
|
drop table t1, t2;
|
|
End of 4.1 tests
|
|
set storage_engine=innodb;
|
|
drop table if exists a;
|
|
drop table if exists A;
|
|
create table A (c int);
|
|
insert into A (c) values (0);
|
|
create table a as select * from A;
|
|
drop table A;
|
|
drop table if exists a;
|
|
set storage_engine=default;
|
|
End of 5.0 tests.
|