How to improve subqueries derived tables performance

(Venu Anuganti) Last week I was working on one of the issue where the sub-query related to OLAP staging was running for about 2+ hours in the production server and finally nailed down to get the query to run in < 7 secs. It was bit interesting and kind of known issue in MySQL sub-queries world and o [membership level="0"] [pmpro_button level="14" text="Read More - Register for Free Membership"][/membership] [membership][standout-css3-button href="http://venublog.com/2010/03/06/how-to-improve-subqueries-derived-tables-performance/" opennewwindow=true]Read More[/standout-css3-button] (Community content)
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