This is a follow-up to my previous post. I have been narrowing down what is
causing this bug. It is a timing issue of a replication ignored table with
an auto-increment primary key values leaking over into a non-ignored table
with inserts immediately after the ignore table has had rows inserted.
Basically, data from the ignored table is corrupting a non-ignored table on
the slave upon immediate inserts.
Here is how to repeat:
On a master issue:
use db;
drop table test;
CREATE TABLE test (id int NOT NULL, cnt int unsigned NOT NULL
AUTO_INCREMENT, PRIMARY KEY (id,cnt) ) ENGINE=MyISAM ;
drop table log;
CREATE TABLE log (id int unsigned NOT NULL AUTO_INCREMENT, log varchar(20),
PRIMARY KEY (id) ) ENGINE=MyISAM AUTO_INCREMENT = 44444;
make sure those two tables are created on the slave through regular
replication.
on slave>
desc test;
desc log;
Once replicated, on the master, add the following line to the [mysqld]
section of my.cnf, and then restart mysql.
replicate-ignore-table=db.log
The on the master, issue the following statements as a copy/paste of all of
them at once.
It's critical that the statements are executed in immediate succession (no
delays)
insert into log values (null,"info1");
insert into log values (null,"info2");
insert into log values (null,"info3");
insert into log values (null,"info4");
insert into test values (1,null);
insert into log values (null,"info5");
insert into test values (1,null);
insert into log values (null,"info6");
insert into test values (2,null);
insert into log values (null,"info7");
insert into test values (2,null);
insert into log values (null,"info8");
Here are the results from the master (all correct):
master>select * from log;
+-------+-------+
| id | log |
+-------+-------+
| 44444 | info1 |
| 44445 | info2 |
| 44446 | info3 |
| 44447 | info4 |
| 44448 | info5 |
| 44449 | info6 |
| 44450 | info7 |
| 44451 | info8 |
+-------+-------+
master>select * from test;
+----+-----+
| id | cnt |
+----+-----+
| 1 | 1 |
| 1 | 2 |
| 2 | 1 |
| 2 | 2 |
+----+-----+
Here are the results from the slave:
slave>select * from log;
Empty set (0.00 sec) <--- as expected, since it is ignored
slave>select * from test;
+----+-------+
| id | cnt |
+----+-------+
| 1 | 44447 | <-- should be "1", but has values from "log" on the master
| 1 | 44448 | <-- should be "2"
| 2 | 44449 | <-- should be "1"
| 2 | 44450 | <-- should be "2"
+----+-------+
If there is the slightest delay between the inserts into "log" and "test",
the replication happens correctly.
Thoughts?
-Hank Eskin
