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Yearly Archives: 2006

Where to get recent MySQL version ?

As you might noticed there are no recent MySQL Community versions available for download from MySQL Download Area This applies both to binaries (which is expected with new polices) but also to the source files …

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MySQL Session variables and Hints

MySQL has two ways to find tune execution of particular query. First is MySQL Hints, such as SQL_BIG_RESULT, STRAIGHT_JOIN, FORCE INDEX etc. You place these directly into the query to change how query is executed …

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Are you designing IO bound or CPU bound application ?

This topic may look boring and obvious but it is extremely important for MySQL Performance Optimization. In fact I probably have to touch it in every second MySQL Consulting work or even more frequently. IO …

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Innodb locking and Foreign Keys

Today I was working with application which uses Innodb and foreign keys and got into locking problems possibly due to foreign keys, so I did a little investigation on that matter. Interesting enough it looks …

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Using LoadAvg for Performance Optimization

Linux and Unixes have excellent metric of system load called “loadavg”. In fact load average is is 3 numbers which correspond to “load average” calculated for one five and 15 minutes. It is computed as …

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COUNT(*) for Innodb Tables

I guess note number one about MyISAM to Innodb migration is warning what Innodb is very slow in COUNT(*) queries. The part which I often however see omitted is fact it only applies to COUNT(*) …

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Interesting MySQL and PostgreSQL Benchmarks

I had found pile of MySQL and PostgreSQL benchmarks on various platforms which I have not seen before. Very interesting reading. It does not share too much information about how MySQL or PostgreSQL was configured …

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BoardReader – Forum Search Engine

One may have notice we were not blogging too much recently, this is because we were quite busy, mainly building BoardReader.com – Search Engine which indexes tens of thousands of forums from all over the …

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Trailing spaces in MySQL

In the past life was easy in MySQL. Both CHAR and VARCHAR types meant the same, only being difference in the sense of fixed or dynamic row length used. Trailing spaces were removed in both …

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Covering index and prefix indexes

I already wrote in the blog as well mentioned in presentation there is often a choice you have to make between having prefix index – which can be significantly smaller in size and having index …

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