Re: Ordering operands of a WHERE clause

Ubiquitous wrote:
>
> I have this SELECT statement in a cursor that's giving me performance
> problems and am wondering if reordering the conditions in the WHERE
> clause would make a difference in performance. Does it help if one
> lists the most restrictive conditions first?

I know it used to in DB2. It won't with any version of Oracle worth running.

If my wild guess is correct, and you are coming from a DB2 background, the bad news is that many of your favorite tricks won't work in Oracle (nor will many Oracle tricks work with DB2). My suggestion is to get some good Oracle based SQL guides and read up there.

If you have already done this, and are stumped, posting your version of Oracle, the query in question, and the DDL for the tables referenced (and their indexes) will be the best way to get some help.

-- 
Phil Singer                |    psinger1ATchartermiDOTnet
Oracle DBA