bzr branch
http://darksoft.org/webbzr/adei/trunk
33
by Suren A. Chilingaryan
Documentation and configuration updates |
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Known problems |
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- MySQL (at least 5.0.45, 5.0.51) has problems with queries dealing with |
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huge rowset. After certain threshold (involving around 500,000 rows) the |
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optimizator stop using INDEXes. |
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* You can check if it is actually happening with 'EXPLAIN <query>' command, |
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* To force usage of indexes it is possible to add "FORCE INDEX (PRIMARY)" |
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keyword after table name in SELECT query. |
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* The $MYSQL_FORCE_INDEXES configuration option is forces usage of indexes |
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when necesary and is intended to fix the described behaviour. |
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