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|
SET @save_timeout = @@GLOBAL.innodb_lock_wait_timeout;
SET GLOBAL innodb_lock_wait_timeout = 1;
SET @save_isolation = @@GLOBAL.tx_isolation;
SET GLOBAL TRANSACTION ISOLATION LEVEL READ COMMITTED;
connection default;
SET SQL_MODE="";
SELECT @@global.tx_isolation;
@@global.tx_isolation
READ-COMMITTED
# keep_locks == 0
GRANT ALL ON test.* TO mysqltest@localhost;
**
** two UPDATE's running and both changing distinct result sets
**
connect thread1, localhost, mysqltest,,;
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
** Get user level lock (ULL) for thread 1
select get_lock("hello",10);
get_lock("hello",10)
1
connect thread2, localhost, mysqltest,,;
connection thread2;
** Start transaction for thread 2
begin;
** Update will cause a table scan and a new ULL will
** be created and blocked on the first row where tipo=11.
update t1 set eta=1+get_lock("hello",10)*0 where tipo=11;
connection thread1;
** Start new transaction for thread 1
begin;
** Update on t1 will cause a table scan which will be blocked because
** the previously initiated table scan applied exclusive key locks on
** all primary keys.
** Not so for READ UNCOMMITTED or READ COMMITTED. The locks that
** do not match the WHERE condition are released.
update t1 set eta=2 where tipo=22;
** Release user level name lock from thread 1. This will cause the ULL
** on thread 2 to end its wait.
DO release_lock("hello");
** Table is now updated with a new eta on tipo=22 for thread 1.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
2 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
** Release the lock and collect result from update on thread 2
DO release_lock("hello");
** Table should have eta updates where tipo=11 but updates made by
** thread 1 shouldn't be visible yet.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
1 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
** Sending commit on thread 2.
commit;
connection thread1;
** Make sure table reads didn't change yet on thread 1.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
2 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
1 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
** And send final commit on thread 1.
commit;
** Table should now be updated by both updates in the order of
** thread 1,2.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
2 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
1 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
** Make sure the output is similar for t1.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
2 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
1 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
2 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
1 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** two UPDATE's running and one changing result set
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
** Get ULL "hello" on thread 1
select get_lock("hello",10);
get_lock("hello",10)
1
connection thread2;
** Start transaction on thread 2
begin;
** Update will cause a table scan.
** This will cause a hang on the first row where tipo=1 until the
** blocking ULL is released.
update t1 set eta=1+get_lock("hello",10)*0 where tipo=1;
connection thread1;
** Start transaction on thread 1
begin;
** Update on t1 will cause a table scan which will be blocked because
** the previously initiated table scan applied exclusive key locks on
** all primary keys.
** Not so for READ UNCOMMITTED or READ COMMITTED. The locks that
** do not match the WHERE condition are released.
update t1 set tipo=1 where tipo=2;
** Release ULL. This will release the next waiting ULL on thread 2.
DO release_lock("hello");
** The table should still be updated with updates for thread 1 only:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 1 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 1 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 1 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
** Release the lock and collect result from thread 2:
DO release_lock("hello");
** Seen from thread 2 the table should have been updated on four
** places.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
1 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
1 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
1 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
commit;
connection thread1;
** Thread 2 has committed but the result should remain the same for
** thread 1 (updated on three places):
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1 1 ccccccccccccccccccccccccccccccccccccccccccc
20 1 ddddddddddddddddddddddddddddddddddddddddddd
1 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 1 fffffffffffffffffffffffffffffffffffffffffff
1 1 ggggggggggggggggggggggggggggggggggggggggggg
60 1 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
1 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
commit;
** After a commit the table should be merged with the previous
** commit.
** This select should show both updates:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1 1 ccccccccccccccccccccccccccccccccccccccccccc
20 1 ddddddddddddddddddddddddddddddddddddddddddd
1 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 1 fffffffffffffffffffffffffffffffffffffffffff
1 1 ggggggggggggggggggggggggggggggggggggggggggg
60 1 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
1 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1 1 ccccccccccccccccccccccccccccccccccccccccccc
20 1 ddddddddddddddddddddddddddddddddddddddddddd
1 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 1 fffffffffffffffffffffffffffffffffffffffffff
1 1 ggggggggggggggggggggggggggggggggggggggggggg
60 1 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
1 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1 1 ccccccccccccccccccccccccccccccccccccccccccc
20 1 ddddddddddddddddddddddddddddddddddddddddddd
1 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 1 fffffffffffffffffffffffffffffffffffffffffff
1 1 ggggggggggggggggggggggggggggggggggggggggggg
60 1 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
1 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** One UPDATE and one INSERT .... Monty's test
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1 (a int not null, b int not null);
insert into t1 values (1,1),(2,1),(3,1),(4,1);
** Create ULL 'hello2'
select get_lock("hello2",10);
get_lock("hello2",10)
1
connection thread2;
** Begin a new transaction on thread 2
begin;
** Update will create a table scan which creates a ULL where a=2;
** this will hang waiting on thread 1.
update t1 set b=10+get_lock(concat("hello",a),10)*0 where a=2;
connection thread1;
** Insert new values to t1 from thread 1; this created an implicit
** commit since there are no on-going transactions.
insert into t1 values (1,1);
** Release the ULL (thread 2 updates will finish).
DO release_lock("hello2");
** ..but thread 1 will still see t1 as if nothing has happend:
select * from t1;
a b
1 1
2 1
3 1
4 1
1 1
connection thread2;
** Collect results from thread 2 and release the lock.
DO release_lock("hello2");
** The table should look like the original+updates for thread 2,
** and consist of new rows:
select * from t1;
a b
1 1
2 10
3 1
4 1
1 1
** Commit changes from thread 2
commit;
connection default;
drop table t1;
**
** one UPDATE changing result set and SELECT ... FOR UPDATE
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
connection thread2;
** Begin a new transaction on thread 2
begin;
** Select a range for update.
select * from t1 where tipo=2 FOR UPDATE;
eta tipo c
20 2 ddddddddddddddddddddddddddddddddddddddddddd
40 2 fffffffffffffffffffffffffffffffffffffffffff
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
connection thread1;
** Begin a new transaction on thread 1
begin;
** Update the same range which is marked for update on thread 2; this
** will hang because of row locks.
update t1 set tipo=1 where tipo=2;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
** After the update the table will be unmodified because the previous
** transaction failed and was rolled back.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
** The table should look unmodified from thread 2.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
** Sending a commit should release the row locks and enable
** thread 1 to complete the transaction.
commit;
connection thread1;
** Commit on thread 1.
commit;
connection thread2;
** The table should not have been changed.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
** Even on thread 1:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** one UPDATE not changing result set and SELECT ... FOR UPDATE
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
connection thread2;
** Starting new transaction on thread 2.
begin;
** Starting SELECT .. FOR UPDATE
select * from t1 where tipo=2 FOR UPDATE;
eta tipo c
20 2 ddddddddddddddddddddddddddddddddddddddddddd
40 2 fffffffffffffffffffffffffffffffffffffffffff
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
connection thread1;
** Starting new transaction on thread 1
begin;
** Updating single row using a table scan. This will time out
** because of ongoing transaction on thread 1 holding lock on
** all primary keys in the scan.
** Not so for READ UNCOMMITTED or READ COMMITTED. The locks that
** do not match the WHERE condition are released.
update t1 set tipo=11 where tipo=22;
** After the time out the transaction is aborted; no rows should
** have changed.
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 11 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
** The same thing should hold true for the transaction on
** thread 2
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
commit;
connection thread1;
commit;
connection thread2;
** Even after committing:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 11 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 11 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** two SELECT ... FOR UPDATE
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
connection thread2;
** Begin a new transaction on thread 2
begin;
select * from t1 where tipo=2 FOR UPDATE;
eta tipo c
20 2 ddddddddddddddddddddddddddddddddddddddddddd
40 2 fffffffffffffffffffffffffffffffffffffffffff
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
connection thread1;
** Begin a new transaction on thread 1
begin;
** Selecting a range for update by table scan will be blocked
** because of on-going transaction on thread 2.
select * from t1 where tipo=1 FOR UPDATE;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection thread2;
** Table will be unchanged and the select command will not be
** blocked:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
** Commit transacton on thread 2.
commit;
connection thread1;
** Commit transaction on thread 1.
commit;
connection thread2;
** Make sure table isn't blocked on thread 2:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
** Make sure table isn't blocked on thread 1:
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** one UPDATE changing result set and DELETE
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
connection thread2;
begin;
delete from t1 where tipo=2;
connection thread1;
begin;
update t1 set tipo=1 where tipo=2;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
commit;
connection thread1;
commit;
connection thread2;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection default;
drop table t1;
**
** one UPDATE not changing result set and DELETE
**
connection thread1;
** Set up table
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
create table t1(eta int(11) not null, tipo int(11), c varchar(255));
insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc");
insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd");
insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee");
insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff");
insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg");
insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh");
insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii");
insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj");
insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk");
connection thread2;
begin;
delete from t1 where tipo=2;
connection thread1;
begin;
** Update on t1 will cause a table scan which will be blocked because
** the previously initiated table scan applied exclusive key locks on
** all primary keys.
** Not so for READ UNCOMMITTED or READ COMMITTED. The locks that
** do not match the WHERE condition are released.
update t1 set tipo=1 where tipo=22;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
20 2 ddddddddddddddddddddddddddddddddddddddddddd
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
40 2 fffffffffffffffffffffffffffffffffffffffffff
50 1 ggggggggggggggggggggggggggggggggggggggggggg
60 2 hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 1 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread2;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 22 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
commit;
connection thread1;
commit;
connection thread2;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 1 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
connection thread1;
select * from t1;
eta tipo c
7 7 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
8 8 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
10 1 ccccccccccccccccccccccccccccccccccccccccccc
30 1 eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
50 1 ggggggggggggggggggggggggggggggggggggggggggg
70 1 iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
80 1 jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
90 11 kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
disconnect thread1;
disconnect thread2;
connection default;
drop table t1;
drop user mysqltest@localhost;
SET SQL_MODE=default;
SET GLOBAL innodb_lock_wait_timeout = @save_timeout;
SET GLOBAL tx_isolation = @save_isolation;
|