> Index the table to hell and back
>>Indexing too many fields, or the wrong combinations, can actualy hurt
>>performance.
>>It's best to put a few benchmarks in place, and add a few indices at a
time.
True.....indexes improve speed of selects but slow down inserts,updates and
deletes as the whole index needs to be rebuilt every time data is changed.
> Never use SELECT *
>>Unless in your database 'select *' is quicker than 'select
>>field,wibble,rar'.
As far as I'm aware SELECT * is quicker than selecting all fields in your
table but if you don't want all the fields then you should be specific as
this will be quicker. However it is still good practice to not use SELECT *
as you may want all of the fields at anyone given time but in 6months time
another developer may have added columns to the table for other purposes
that you don't need in your select statement
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-----Original Message-----
From: Thomas Chiverton [mailto:[EMAIL PROTECTED]]
Sent: 25 July 2001 13:06
To: CF-Talk
Subject: RE: SQL Query
> Index the table to hell and back
Indexing too many fields, or the wrong combinations, can actualy hurt
performance.
It's best to put a few benchmarks in place, and add a few indices at a time.
> Never use SELECT *
Unless in your database 'select *' is quicker than 'select
field,wibble,rar'.
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