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SQL Server Query Processing Puzzle: LIKE vs ?

How creative are you with manipulating your queries to produce more efficient plans? Try the following puzzle and e-mail your solution to me at [ @ pythian.com]. Make sure to include an explanation of why it works, as well as your mailing address. The best two solutions/explanations win a free copy of Expert SQL Server 2005 Development, a wonderful feeling of accomplishment, plus eternal fame and glory when I reveal your solutions here on the blog.

MySQL Plug-in for Oracle Grid Control Announced, Released

Reading PlanetMySQL today, I discovered that Alex Gorbachev’s announcement that he has released the first public beta of his Oracle Grid Control plugin for MySQL was not aggregated! Knowing that my feed is aggregated, and not willing to let this news and this amazing work go unnoticed by the MySQL community during the conference (I am at MySQLConf listening to Amazon.com’s CTO speak right now!) you can access the update here.

Recent Spike Report from v$active_session_history (ASH)

sec p, dsk p, gets p, rows p, cpu p — these are average statistics for the query being executed. This should give you a quick overview of whether the query is a big query, a small query, a CPU-intensive or a disk I/O-intensive query. Be careful: since the query was introduced to the shared pool, those columns are averages, and therefore could be misleading. These are all per execution stats, so sec p represents the number of seconds on average it took to execute the query.

MySQL Plug-in 0.42 for Oracle Grid Control: First Beta Released

has finally happened! The first public release of the MySQL plug-in for Oracle Enterprise Manager 10g Grid Control is out. In the last few months, more and more people showed interest in the potential plug-in, and even few guys from Oracle contacted me independently of each other with their own reasons to have a MySQL plug-in available. This interest accelerated the fermentation of thoughts in my brain, and I got down to work. Pythian generously sponsored my development time. Here are the details. The first release version is 0.42 because that’s obviously the perfect number to start something good.

MySQLConf Pythian “Birds of a Feather” Invitation

I am finally able to announce when and where the Pythian BoF session has been scheduled! It will be in the Alameda room, 7:30-8:30pm on Tuesday, April 15th. The session, titled “Ask the Pythian Maestro”, will be attended by myself and our two MySQL team leads, Sheeri K. Cabral and Augusto Bott.

Can’t Make the MySQL Conference? Join Me Live!

If you can’t attend the MySQL Conference, you can still virtually attend. 2-3 pm PDT on Tuesday, April 15th for the “Best Practices for Database Administrators” session, and, 11:55 am -12:40 pm PDT on Thursday, April 17th for the “Database Security Using White-Hat Google Hacking” session. You need nothing but your web browser; unlike some other live meetings, audio streams from the website too, so there’s no phone number to call or participant code or anything. There’s also a live chat so you can participate and ask questions while the session is going on.

Multi-Column Correlation and Extended Stats in Oracle 11g

We all have encountered this situation many times before: the cost-based optimizer assumes no correlation between two columns (until 11g), and this has the effect of erroneously reducing the cardinality of a row source. Incorrect cardinality estimates are one of many root causes for SQL performance issues. Consider the following example.

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