williamvdw2004 wrote:

>Is there a difference in speed for indexes of different field types.
>
>eg. select * from transactions where transno = '1234'
>
>Will firebrid return this record quicker when transno is numeric or
>varchar?
>
>Does the datatype make a difference?
>
>Regards
>William
>
>

I can just think of the difference in size...

a 4 byte integer should have similar performance to a 4 byte char/varchar.

But a 40 byte char/varchar field should be a bit (maybe just noticeable
on millions records when you got more than 2 or 3 pages deep) slow than
a 4 byte integer, since the key size will be larger, less index entries
will fit on each index page...

see you !

--

Alexandre Benson Smith
Development
THOR Software e Comercial Ltda.
Santo Andre - Sao Paulo - Brazil
www.thorsoftware.com.br