Hi Dan,
Thanks for yur response. Does it makes sense to create an index on a
primary key ..as that is my smallest field ?
Regards
Prasad
-----Original Message-----
From: Dan Nelson [mailto:dnelson@stripped]
Sent: Monday, September 04, 2006 9:53 AM
To: Prasad Ramisetti (WT01 - Broadband Networks)
Cc: dmagick@stripped; mysql@stripped
Subject: Re: problem with InnoDB
In the last episode (Sep 04), prasad.ramisetti@stripped said:
> Actually there is some requirement, where I need to know the number of
> rows that I will get for my queries before actually executing the
> query. Could you please suggest some way for this.
Your best bet is to create an index on the smallest column you can find
(maybe even create a char(1) and leave it empty), and "SELECT COUNT(*)
FROM innotable USE INDEX (smallcolumn)". That way mysql only has to
scan a small secondary index instead of the main table index.
--
Dan Nelson
dnelson@stripped
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