topic Re: FK-PK - better performance in Developers

FK-PK - better performance

jplarios — Thu, 27 Aug 2009 13:40:49 GMT

Hi:
question:
I know that indexes are automatically built when creating , say, a FK to PK relation. And it is clear that indexes allow for the enforcement of rules when incoming rows are getting updated or coming in. My question is if having a FK to PK relation will increase performance when querying versus having plain indexes in both tables without IC. If there is a performance increase that the table with the FK does not need to consult its index but uses the PK index? Is there any performance boost when having IC as opposed to simple indexes?
Thanks
jp

Re: FK-PK - better performance

Vince_SAS — Thu, 27 Aug 2009 13:51:46 GMT

This forum is restricted to discussion of SAS Stored Processes.

http://support.sas.com/documentation/cdl/en/stpug/61271/HTML/default/a003152554.htm

You might want to search support.sas.com for an answer to your question. Here is one page you might find helpful:

http://support.sas.com/documentation/cdl/en/lrcon/61722/HTML/default/a000403555.htm

Vince DelGobbo
SAS R&D

Re: FK-PK - better performance

LinusH — Fri, 28 Aug 2009 07:43:22 GMT

The main application for IC is updating tables, not querying.
I have seen no examples nor documentation that indicates that the SQL/WHERE-planner takes IC into account.
So my qualified guess is no, there is probably be no difference.
/Linus