MySQL com_select?

Posted by symcbean on Server Fault See other posts from Server Fault or by symcbean
Published on 2012-03-28T17:00:56Z Indexed on 2012/03/28 17:33 UTC
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Filed under:

mysql

|

cache

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tuning

I'm looking to tune my query cache a bit. According to 7.6.3.4. Query Cache Status and Maintenance in the manual:

The Com_select value is given by this formula: Qcache_inserts + Qcache_not_cached + queries with errors found during the column-privileges check

However in 5.1.5. Server Status Variables it suggests that this is maintained by the DBMS. Having said that

mysql> show status like 'Com_select%';

Always returns a value of 1 - and I'm pretty sure I've run more than one non-cached select query on my database since it started.

It looks as if other people are similarly confused.

Is this status variable redundant? Which bit of the manual is wrong?

TIA

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