[TYPO3-dev] Testing TYPO3 caching vs.[FE][pageCacheToExternalFiles]

["Marc Wöhlken [quadracom]"]

Martin Schoenbeck schrieb:

> Maybe you simply misunderstood it. Explain tells you when mysql is going to
> do a full table scan instead of using an index due to such a condition.

Yes, that was a mistake as the behavior of explain did change with mysql
version 4+.

BTW: The old rule of thumb that a full table scan is done when a result
set contains more than 30% of all table rows is not valid any more, too.
The mysql manual states that more sophisticated algorithms (what ever
that means ;-) are used to predit wheter a full scan is better than
doing random disk access.

Back to the mysql manual
 Marc


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Marc Wöhlken

Quadracom - Gottschall, Proffe & Wöhlken

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