Subject Re: [firebird-support] Index speeds For different field types
Author Alexandre Benson Smith
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
>Does the datatype make a difference?
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
THOR Software e Comercial Ltda.
Santo Andre - Sao Paulo - Brazil