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Displaying posts with tag: binlogs (reset)
Streaming MySQL binary logs for backup

With MySQL it is relatively easy to create point in time restores. All you need is a recent(ish) backup, and a bunch of saved binary logs. You can restore the backup you have, and when it is completed, you can use mysqlbinlog utility to apply your saved binary logs to the desired state of your database. I […]

Avoid clear text passwords in MySQL logging.

What happens when you use the PASSWORD() function to insert a password hash into a table?

  • The hash will be written to the table
  • The password might be written in clear text to the binlog
  • The password might be written in clear text to the general log
  • The password might be written in clear text to the slow query log

The query

mysql [localhost] {msandbox} (test) > INSERT INTO testpwd(pwd) VALUES(PASSWORD('secret_password'));
Query OK, 1 row affected (0.00 sec)


The General log

130128 16:04:41     1 Query     INSERT INTO testpwd(pwd) VALUES(PASSWORD('secret_password'))


The Slow query log

# Time: 130128 16:04:41
# User@Host: msandbox[msandbox] @ localhost []
# Query_time: 0.004887 Lock_time: 0.001043 Rows_sent: 0 Rows_examined: 0
SET …
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Initial Reactions to MySQL 5.6

New versions of MySQL are always interesting to try out. Often they have features which I may have asked for myself so it’s satisfying to see them eventually appear on a system I use. Often other new features make life easier for the DBA. Finally we hope overall performance will improve and managing the server(s) will be come easier.

So I had a system which needs to make heavy writes, and performance was a problem, even when writing to SSDs. Checkpointing seemed to be the big issue and the ib_logfile size in MySQL 5.5 is limited to 4 GB. That seems a lot, but once MySQL starts to fill these files (and this happens at ~70% of the total I believe),  checkpointing kicks in heavily, and slows things down.  So the main reason for trying out MySQL 5.6 was to see how things performed with larger ib_logfiles. (Yes, MariaDB 5.5 can do this too.)

Things improved a lot for my specific workload which was great news, but one thing …

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Statement-based vs Row-based Replication

Replication as most people know it, has mostly been SQL statement propagation from master to slave. This is known as "statement-based" replication. But there is also another kind of replication that is available, "the row-based replication" and that has quite a lot of benefits. In this post I intend on highlighting the advantages and disadvantages of both the types of replication to help you choose the best one. I also follow up with my own recommendation.

Showing entries 1 to 4