[CentOS] Centos/Linux Disk Caching, might be OT in some ways

JohnS jses27 at gmail.com
Thu Jan 28 04:29:11 UTC 2010


On Wed, 2010-01-27 at 10:10 -0600, Les Mikesell wrote:

> 
> I've seen mysql do some really stupid things, like a full 3-table join 
> into a (huge)disk temporary table when the select had a 'limit 10' and 
> was ordered by one of the fields that had an index.

Very true. You can you use logic operations to build up "Tree Sets" as
Temp Tables on disk and in RAM using Inner and Outer Joins and Index
them the way you see fit.  This I have done on Innodb.  These methods
work on many "List" types like Edge and Adjacency Modling.   I did all
the hard work on mssql then to innodb I went, which now was a big
mistake.  Basically it comes to a select, then the select gets built up
into the rational you need of a temp table structure tree.

John



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