Several Small, Specific, MySQL Query Cache Questions

Posted by Robbie on Stack Overflow See other posts from Stack Overflow or by Robbie
Published on 2010-04-09T13:10:46Z Indexed on 2010/04/09 13:13 UTC
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I've look all over the web and in the questions asked here about MySQL caching and most of them seem very non-specific about a couple of questions that I have about performance and MySQL query caching. Specifically I want answers to these questions, assume for all questions that I have the query cache enabled and it is of type 2, or "DEMAND":

Is the query cache per table, per database, or per server? Meaning if I have the cache size set to X and have T tables and D databases will I be caching TX, DX, or X amount of data?
If I have table T1 which I regularly use the SQL_CACHE hint on for SELECT queries and table T2 which I never do, when I query T2 with a SELECT query will it check through the cache first before performing the query? *Note: I don't want to use the SQL_NO_CACHE for all T2 queries.*
Assume the same situation as in question 2. If I alter (INSERT, DELETE) table T2 will any processing be done on the cache?
For answers to 2 and 3, is this processing time negligible if T2 is constantly being altered and is the target of a majority of my SELECT queries?

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