Re: Tuning question: functions vs.self joins

Hi Sunita,

Don't use functions with selects to replace joins. Experience dictates function are treated as recursive sql, so as a separate pass, and will be optimised separately. In my previous job, in an application I didn't develop, the results proved to be disastrous. Full table scans all over the place!
Self joins should be efficient enough as long as there is proper indexing of this tables.
Or maybe you could post an example

Hth
Sybrand Bakker, Oracle DBA

sunita_at_postoffice.worldnet.att.net wrote:

> The application I am working on has many big queries
> with self joins to a table with 9000 rows.
>
> ARe the queries supposed to work faster if the self joins
> are replaced with functions?
>
> I wrote teh functions and changed teh queries and found that
> performanc eimprovement was NIL.
>
> What is your opinion? IS there a better way to
> improve the performance of queies with self joins.
>
> --
> SUnita
Received on Sat Aug 15 1998 - 09:53:37 CDT