Re: Outer join -> Union
- From: Gints Plivna <gints.plivna@xxxxxxxxx>
- To: Petr.Novak@xxxxxxxxxxxx
- Date: Fri, 5 Nov 2010 11:52:33 +0200
BTW I hope that in your real test case you have defined columns as NOT
NULL. That can make difference sometimes in index (not) usage :)
I also tried your examples with columns as NOT NULLS, but the best I
could achieve was INDEX FULL SCAN or FAST FULL INDEX SCAN, and these
wasn't better (in terms of logical reads) than 2 full scans and hash
join.
Gints Plivna
http://www.gplivna.eu
2010/11/5 Petr Novak <Petr.Novak@xxxxxxxxxxxx>:
> Hallo Dion,
>
> I have found two Notes in Metalink:
>
> Bug 7345484 - Left outer join with filters are slow [ID 7345484.8]
> CBO Chooses Poor Plan In 10.2.0.4/11.1.0.6 When Outer Joining [ID 727604.1]
--
//www.freelists.org/webpage/oracle-l
Other related posts:
