Re: Join/Datatype Performance Considerations

randyd_at_cais3.cais.com (Randy Dewoolfson) wrote:
>KevinWaters_at_DRS_at_CPLISD wrote:
>: Is anyone aware of a performance differential in joining two tables on VARCHAR2 columns versus joining them on NUMERIC columns?
>
>Here's a real non-technical answer for ya-
>use numbers.
>If you're a computer you can easily check two numbers...
>you need to check each character in a string one by one in a loop...
>The varchars will be slower...
>Randy :)

Hey! If I remember my days of assembly programming, characters and numbers are all bytes! I mean: if you're comparing 38 digit numbers and 2 characters strings, I think that string comparison will be faster. And remember that Oracle stores numbers up to 38 digits that means that the 32bit CPU arithmetic is not able to handle the numbers and specific routines are necessary to compare numbers.

Regards,

Carlos Netto
cnetto_at_cps.softex.br Received on Sat Jan 06 1996 - 00:00:00 CET