As previously mentioned, Darren Cassar has been working on a new automated installer for the DBbenchmark program. It’s now available for download: click here. All you need to do is save it to the directory that you want to install to and then make sure it’s executable: “chmod 700 installer.sh”, then run it “./installer.sh”.

The development cycle is moving right along for the community’s newest MySQL benchmarking script. I’m pleased to announce that we now officially support FreeBSD (version 8.1 tested) so go ahead and download now and test your FreeBSD, Linux, or OSX MySQL server! Click here for the download.

Courtesy of Darren Cassar and some generous coding this weekend, we’re going to be releasing a auto-installer / updater for the application which you can use to automate that part of the process. Stay tuned for information on that release.

In a test lab, we ran into a situation where the connection between our Cisco Access Registrar (AAA) server and MySQL server was timing out. This forced the server to reconnect and resulted in the following errors: name/radius/1 Error Server 0 ODBC client (DataSource 'my_odbc', Connection 8): SQLExecute failed: SQLState:08S01 NativeError:2006 ErrorText:[MySQL][ODBC 3.51 Driver][mysqld-5.0.21-log] MySQL […]

We ran across the following error on a MySQL slave server recent: mysql> SHOW SLAVE STATUS \G <snip> Last_Error: Query caused different errors on master and slave. Error on master: 'Deadlock found when trying to get lock; try restarting transaction' (1213), Error on slave: 'no error' (0). Default database: '<database_name>'. Query: '<query>' <snip> In this […]

The MySQL query cache can be very useful in environments where data is not modified often, and traffic consists of mostly reads. It can improve performance by quite a bit if used correctly, but can actually degrade performance if configuration, queries, and traffic patterns are not optimized for it.

Let me quickly go over what the query cache is, and what it is not. The query cache does not cache the query execution plan, the full page on disk (which is what the InnoDB buffer pool is used for), DDL statements, or any queries that modify data (INSERT/UPDATE/etc). The query cache *does* cache the full result set of “cacheable” SELECT queries. For a query to be “cacheable”, it must have the following properties:

• It must be deterministic. The query must return the same result set each time that it is run. This means that it may not contain any non-deterministic variables, such as …

Even though Data warehouse is picking very rapidly in the last year or so, but few companies who are already made a right mark in the right time could not[...]

You take a look at someone’s MySQL (or MariaDB) data directory, and see

mysql
foo
bar -> foo

1. What’s the issue? Identify pattern.
2. What does it mean?  Consequences.
3. Is there any way it can be safe and useful/usable? Describe.

Good luck!

Last week I was working on EC2 MySQL server where one of the slave is taking lot of time to catch-up; and only job that is running on that server[...]

Last month, I blogged about a case involving InnoDB, where all threads acting on InnoDB tables completely stuck for about few hours doing nothing; until we found a way to[...]