When examining MySQL configuration, we quite often want to know how various buffer sizes are used. This matters because some buffers (sort_buffer_size for example) are allocated to their full size immediately as soon as they are needed, but others are effectively a “max size” and the corresponding buffers are allocated only as big as needed [...]
Recover BLOB fields
July 1, 2010 By 4 Comments
For a long time long types like BLOB, TEXT were not supported by Percona InnoDB Recovery Tool. The reason consists in a special way InnoDB stores BLOBs. An InnoDB table is stored in a clustered index called PRIMARY. It must exist even if a user hasn’t defined the primary index. The PRIMARY index pages are [...]
When should you store serialized objects in the database?
January 21, 2010 By 47 Comments
A while back Friendfeed posted a blog post explaining how they changed from storing data in MySQL columns to serializing data and just storing it inside TEXT/BLOB columns. It seems that since then, the technique has gotten more popular with Ruby gems now around to do this for you automatically.
Should you move from MyISAM to Innodb ?
January 12, 2009 By 59 Comments
There is significant portion of customers which are still using MyISAM when they come to us, so one of the big questions is when it is feasible to move to Innodb and when staying on MyISAM is preferred ? I generally prefer to see Innodb as the main storage engine because it makes life much [...]
Quickly preloading Innodb tables in the buffer pool
May 1, 2008 By 9 Comments
In the previous post I mentioned a way I use to preload Clustered Index (data) for Innodb tables. Though I thought this topic would benefit from a bit more information. But lest first start with feature request for Innodb Team: All ways I mention here are hacks and they can’t be as efficient as native [...]
Real-Life Use Case for “Barracuda” InnoDB File Format
April 23, 2008 By 11 Comments
In one of his recent posts Vadim already gave some information about possible benefits from using new InnoDB file format but in this post I’d like to share some real-life example how compression in InnoDB plugin could be useful for large warehousing tasks.
Idea: Couple of more string types
April 18, 2008 By 12 Comments
MySQL has a lot of string data types – CHAR, VARCHAR, BLOB, TEXT, ENUM and bunch of variants such as VARBINARY but I think it is not enough I would also like to see type HEXCHAR which would be able to store hex strings, such as those returned as MD5() and SHA1() efficiently. With little [...]
State of MySQL Market and will Replication live ?
April 9, 2008 By 29 Comments
There are interesting posts these day about future of MySQL Replication by Brian Frank and Arjen. I think it very interesting to take a look at a bit bigger picture using framework from Innovators Dilemma and Innovators Solution. I’m not going to speak about disruption and commoditisation of Database Market, leaving this for Market talks, [...]
Data Recovery Toolkit for InnoDB Version 0.1 Released
November 26, 2007 By 6 Comments
As Peter mentioned in one of previous posts, we’ve done huge work developing robust strategies of InnoDB data recovery to provide our customers effective data recovery services and one of major parts of these strategies is our toolkit for InnoDB data recovery. Today I’m proud to announce its first public release which was used to [...]
10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
People are sometimes contacting me and asking about bugs like this which provide a trivial way to crash MySQL to the user with basic privileges and asking me what to do. My answer to them is – there is nothing new to it and they just sit should back and relax Really – there are [...]
