Re: Newbie help with explain plans

From: Anurag Varma <avdbi_at_hotmail.com>
Date: Thu, 04 Sep 2003 00:46:25 GMT
Message-ID: <BXv5b.1601$1w4.1400@news02.roc.ny>

"vipan" <dba_at_no_spam.netscape.net> wrote in message news:3F5602FE.6000609_at_no_spam.netscape.net...
> Hi,
>
> Even if you have statistics and don't have necessary indexes Full table
> scan will heppen. And statistics don't make oracle to get row by rowid
> as we see in Fast Explain Plan.
>
> Thanks

Vipan,

You missed the point Jim is making ...
The slow query is using hash joins etc... The fast query is using purely nested loops.

His gut feeling could be right on spot. Fast query seems to be working on "no statistics" or using RBO.

Of course its a gut feeling ..... so it might not be the actual case.

There could be many reasons why explain plans are different. Your hypothesis is also a guess (i.e. not necessarily true).

Anurag Received on Wed Sep 03 2003 - 19:46:25 CDT