Re: Strange Oracle Optimization

Kin Ng wrote:

> Actually the query returns LOTs of rows. It just took a long time
> (and err out) for a Large set of rows. I started trying to do ROWNUM
> = 1 and it returned FAST. Then I tried ROWNUM < 1000 and it returned
> a thousand rows fast. Then I tried ROWNUM < 10,000, then 1 million
> and finally ROWNUM > 0 and ALL cases it returned lots of rows and
> FAST.
>
> > > Why adding this makes a query run so much faster?

To answer your question requires running EXPLAIN PLAN on both versions ... with and without the added clause.

BTW: Something you should be doing with every SQL statement you write.

--
Daniel Morgan
http://www.outreach.washington.edu/extinfo/certprog/oad/oad_crs.asp
damorgan_at_x.washington.edu
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