Re: VARCHAR -vs- CHAR: huge performance difference?

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От V i s h a l Kashyap @ [Sai Hertz And Control Systems]
Тема Re: VARCHAR -vs- CHAR: huge performance difference?
Дата
Msg-id 40D04296.5060103@sancharnet.in
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Ответ на VARCHAR -vs- CHAR: huge performance difference?  ("C. Bensend" <benny@bennyvision.com>)
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Dear C. Bensend wrote:

>   I am parsing and storing emails, so I have a lot of character string
>data to worry about.  In one particular table, I have 26 columns of type
>varchar, with widths of 24-8192 characters.  This is the table that is
>giving me some pretty severe performance problems.
>
>   For example, many of the statistics I run against these emails is a
>simple count(), whether it be on a column or *.  Right now, counting the
>rows takes in excess of 3.5 seconds.  OK, that's pretty slow.  However,
>there are only --> 24,000 <-- rows in this table!  I could see it taking
>a long time if I had 500,000 rows, or a million, but 24,000?
>
>
>
For similar  post someone suggested to do a count like

select count(*)  from table where any = any limit 1 ;

Try this look if thiers any  performance increase.

--
Regards,
Vishal Kashyap
Director / Lead Software Developer,
Sai Hertz And Control Systems Pvt Ltd,
http://saihertz.rediffblogs.com
Yahoo  IM: mailforvishal[ a t ]yahoo.com


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