Re: Is there a way to speed up Large database searches in SQL?

Lawrence Watkins Work ( (no email) )
Tue, 5 May 1998 09:24:17 -0500

I have a scheduled task that figures out all of my users
time online once an hour then writes that to a table
including the current month and login name. Then when the
users check time online it comes from the much
smaller/faster table.
Lar
-----Original Message-----
From: Jeff Binkley <jeff.binkley@asacomp.com>
To: ntisp@emerald.iea.com <ntisp@emerald.iea.com>
Date: Monday, May 04, 1998 11:53 PM
Subject: Is there a way to speed up Large database searches
in SQL?

>-> Maybe someone could help me on speeding up SQL Searches.
We would like to
>-> offer a from - to period search on our database so our
clients can view
>-> their time online. The one problem we are having due to
our Huge database
>-> is that it can take several minutes for the results to
appear. Is there any
>-> SQL Command that will stop searching after the specified
date had passed?
>-> For example:
>->
>-> Our database has information from December 97... and we
would like to do a
>-> search from say January to February. But when we run
the SQL Query it scans
>-> the WHOLE Database... Is there any way of telling SQL to
stop searching
>-> after it Finds March?
>
>What you are talking about is a table scan. That is not
how you want to
>search SQL databases. You need an index which covers the
fields you are
>searching on and a query which is written so as not to
force the SQL server
>to do table scans when looking for data. Without seeing
the SQL code or
>knowing what SQL server you are using (i.e. Sybase, MS SQL,
oracle etc..), it
>is difficult to be more specific.
>
>Now there is a downside to indexes, especially if you go
"index happy", slow
>inserts. This is beacuse every index needs to be updated
when a record is
>inserted. Also you may want to setup period index
rebuilding on tables
>which have regular large amounts of inserts. This can help
with indexes
>becoming fragmented on the drives.
>
>
> Jeff Binkley
> ASA Network Computing
>
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