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Old May 9th, 2006, 11:29 AM
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Default plz recommend...

I want to improve my queries knowledge lz suggest me wot i do...


Wot is the difference between using joins to get data from more than one tables and using subqueries to do same. when to use what.
i'll b thankful to whom reply

 
Old July 10th, 2006, 06:31 AM
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when you need to retrive the data from more than one columns of multiple tables then use joins.otherwise use subquery.if you want improve the query knoladge then use books online and start practicing the example given there.

 
Old August 25th, 2006, 05:49 AM
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Basically using subquery than joins mostly results in performance degradation, however using subqueries for smaller tables is fine while for larger tables go for joins (because subqueries may introduce internal worktables which is an extra overhead) !

Harsh Athalye
India
"Nothing is impossible"





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