Of course it will do full table scans! You're not limiting your join
to any set of values, you are trying to read two whole tables. Because
of the multiblock reads, full table scans and hash join will be more
efficient
then a nested loops plan where one table is read sequentially and the other
is read thru the PK index. Optimizer made the rigtht decision.
> -----Original Message-----
> From: Venu Gopal Andem [mailto:venu.andem_at_wipro.com]
> Sent: Tuesday, February 04, 2003 11:09 PM
> To: Multiple recipients of list ORACLE-L
> Subject: Full table scan
>
>
> List,
>
> I have the following scnario:
>
> I'm doing a select from 2 tables joining them using a primary key- ref
> key on the tables and the explain plan is showing 2 full
> table scans...
> Even after analyzing the tables and the Optimizer mode is set
> to CHOOSE.
>
> SELECT a.col1, b.col2
> FROM table1 a, table2 b
> WHERE a.col1 = b.col1
>
> Any comments...
>
> Thanks in advance,
> Venu
>
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Received on Wed Feb 05 2003 - 09:33:38 CST
