May 23, 2013

MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown

March 14, 2013 By 2 Comments

While preparing the webinar I will deliver this Friday, I ran into a quite interesting (although not very impacting) optimizer issue: a “SELECT *” taking half the time to execute than the same “SELECT one_indexed_column” query in MySQL 5.6.10. This turned into a really nice exercise for checking the performance and inner workings of one [...]

Filed Under: Events and Announcements, Insight for Developers, MySQL Tagged With: , ,

InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

March 4, 2013 By 7 Comments

This is part 2 in a 3 part series. In part 1, we took a quick look at some initial configuration of InnoDB full-text search and discovered a little bit of quirky behavior; here, we are going to run some queries and compare the result sets. Our hope is that the one of two things [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By 1 Comment

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

Percona Server on the Raspberry Pi: Your own MySQL Database Server for Under $80

February 25, 2013 By 10 Comments

There are many reasons for wanting a small MySQL database server: You’re a uni student who wants to learn the SQL language better and needs a mini-testbox You’re a Windows user who wants to play around with Percona Server on Linux You’re a corporate application developer who wants a small SQL development & test box [...]

Filed Under: Hardware and Storage, Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , ,

Analyzing Slow Query Table in MySQL 5.6

February 18, 2013 By 1 Comment

Next week I’m teaching an online Percona Training class, called Analyzing SQL Queries with Percona Toolkit.  This is a guided tour of best practices for pt-query-digest, the best tool for evaluating where your database response time is being spent. This month we saw the GA release of MySQL 5.6, and I wanted to check if any [...]

Filed Under: Events and Announcements, Insight for DBAs, Live Virtual Training, MySQL, Percona Toolkit, Training Tagged With: , , , , , , ,

Implications of Metadata Locking Changes in MySQL 5.5

February 1, 2013 By 9 Comments

While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the Metadata Locking related changes that were introduced in MySQL 5.5.3. It appears that the implications of Metadata Locking have not [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , , ,

SQL Injection Questions Followup

July 26, 2012 By 2 Comments

I presented a webinar today about SQL Injection, to try to clear up some of the misconceptions that many other blogs and articles have about this security risk.  You can register for the webinar even now that I’ve presented it, and you’ll be emailed a link to the recording, which will be available soon. During [...]

Filed Under: Insight for Developers, MySQL

Announcing Percona Server 5.5.25a-27.1

July 21, 2012 By Leave a Comment

Percona is glad to announce the release of Percona Server 5.5.25a-27.1 on July 21st, 2012 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.25a, including all the bug fixes in it, Percona Server 5.5.25a-27.1 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release can [...]

Filed Under: MySQL

STOP: DELETE IGNORE on Tables with Foreign Keys Can Break Replication

February 2, 2012 By 1 Comment

DELETE IGNORE suppresses errors and downgrades them as warnings, if you are not aware how IGNORE behaves on tables with FOREIGN KEYs, you could be in for a surprise. Let’s take a table with data as example, column c1 on table t2 references column c1 on table t1 – both columns have identical set of rows for [...]

Filed Under: Insight for DBAs

Avoiding auto-increment holes on InnoDB with INSERT IGNORE

November 29, 2011 By 8 Comments

Are you using InnoDB tables on MySQL version 5.1.22 or newer? If so, you probably have gaps in your auto-increment columns. A simple INSERT IGNORE query creates gaps for every ignored insert, but this is undocumented behaviour. This documentation bug is already submitted. Firstly, we will start with a simple question. Why do we have [...]

Filed Under: MySQL
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