Shell Tips !

Here is a quick picture about the impact of MySQL indexes misuse. At work, our developers made a new release of their search engine using MySQL fulltext indexes, unfortunately they didn’t implement it correctly. The impact was a huge load on all our database servers. To find the trouble, I had to redirect the SQL search flow to a specific server and check for the slow queries then reproduce it with EXPLAIN. Don’t need a long time to find that the search query did an invalid usage of the fulltext index and the “Match / Against” syntax. In fact, the fulltext index was a multiple column fulltext index, in such case you have to specify ALL the column present in your index, else the index won’t be used by MySQL…

If you are a PHP developer or a LAMP server admin you probably have already heard about the Zend Platform. After some test and configure/tunning step, we deployed this solution on a heavy loaded production server running with Apache 2.x, PHP 4.4.x, MySQL Client 5.x.

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Here is a quick post of a “quick and dirty” patch for the ISC DNS Server : Bind 9.5.0a6 and its dlz mysql driver. For the quick story, I was using Bind 9.4.1 with dlz MySQL. My MySQL server is a 5.0.41 (with solidDB). While using it, I realize that some times the dns server was returning empty value for the dns queries. I tried many tips but it was still (sometime) giving me empty answer… Of course, I suspected the dlz driver. So, I tried to upgrade to Bind 9.5.0a6 but the problem still happened and the only way to fix was to restart bind !

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