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Re: Simple Query - but explain worries me
Posted by: Jake Day
Date: November 01, 2005 07:37AM

Vangelis,

Header returns 36978

Detail returns 400798

i've also done a quick

select * from racedetail b where b.race_id not in (select a.race_id from raceheader a)

this returned 0 rows, thus definitely assuring me that there are no "orphans". (I tried to write a NOT EXISTS....but either my query writing is rusty(likely) or EXISTS works differently....)

I'm finding more and more issues though as i'm building queries that aren't "optimising" the way i'd expect them too....its possible(some might say probable!) that its due to my indexing, but most are fairly simple, so i am concerned :(


Update: - I've just checked the EXISTS stuff.....as suspected it was my rusty query writing. NOT EXISTS also returns 0 rows)



Edited 1 time(s). Last edit at 11/01/2005 07:43AM by Jake Day.

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