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does query speed depend on the number of coloms?

Hi,

I was wandering.
Does the query speed also depend on the colums that you don't use in the
query (so not in the where and not in the select part).

I have a lange unused backup field in every row.
I only put the backup information into that field once.
But never use it on my live database.

Does it speed up my queries if I put the backup information into an other
table?

Thanks,
Wouter
Jul 20 '05 #1
2 1833
"nospam_nopriva" wrote:
Hi,

I was wandering.
Does the query speed also depend on the colums that you don't
use in the
query (so not in the where and not in the select part).

I have a lange unused backup field in every row.
I only put the backup information into that field once.
But never use it on my live database.

Does it speed up my queries if I put the backup information
into an other
table?

Thanks,
Wouter


Don’t think so. Of course, there is a bit of overhead to gather that
data, and send it to the client app... but it should be very small
compared to other things that bring the performance down.

I have found the main performance drag to be not having proper
indecis.

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Jul 20 '05 #2
thanks!
:-)

Wouter

"steve" <Us************@dbForumz.com> wrote in message
news:41********@news.athenanews.com...
: "nospam_nopriva" wrote:
: > Hi,
: >
: > I was wandering.
: > Does the query speed also depend on the colums that you don't
: > use in the
: > query (so not in the where and not in the select part).
: >
: > I have a lange unused backup field in every row.
: > I only put the backup information into that field once.
: > But never use it on my live database.
: >
: > Does it speed up my queries if I put the backup information
: > into an other
: > table?
: >
: > Thanks,
: > Wouter
:
: Don't think so. Of course, there is a bit of overhead to gather that
: data, and send it to the client app... but it should be very small
: compared to other things that bring the performance down.
:
: I have found the main performance drag to be not having proper
: indecis.
:
: --
: http://www.dbForumz.com/ This article was posted by author's request
: Articles individually checked for conformance to usenet standards
: Topic URL:
http://www.dbForumz.com/mySQL-query-...ict167416.html
: Visit Topic URL to contact author (reg. req'd). Report abuse:
http://www.dbForumz.com/eform.php?p=561579
Jul 20 '05 #3

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