Why pt-table-checksum diffs 0 while my master and slave are certainly different?


pt-table-checksum :2.2.14
MySQL:5.6.19
Binlog:row


Master:
mysql> select * from test.gf;
+------+
| id |
+------+
| 2 |
| 5 |
| 7 |
+------+
Slave:

mysql> select * from test.gf;
+------+
| id |
+------+
| 7 |
+------+

So master and slave are certainly different,but running pt-table-checksum shows no difference:


./pt-table-checksum h=localhost,u=root,p=PASSWORD,P=3306
......
other table checking result
......
06-09T10:55:31 0 0 3 1 0 0.003 test.gf

And percona.checksums table in slave shows difference crc:


select * from percona.checksums;
......
other output rows
......
| test | gf | 1 | 0.000625 | NULL | NULL | NULL | [B]46156dca [/B]| 1 | [B]435a7b4f [/B]| 3 | 2015-06-09 10:55:31 |

My question is since percona.checksums table in slave shows that crc checking diffs in master and slave ,why pt-table-checksum report’s diffs column shows 0?

I found the reason, because DSN’s username(root) just could login to master but couldn’t login to slave, but shouldn’t pt-table-checksum give an alert other than just showing diffs 0?

Hi leafonsword;

That would probably be worth submitting as a bug for logging improvement.

https://bugs.launchpad.net/percona-toolkit

-Scott