Re: newbie : getting rid of IN clause

From: <dn.perl_at_gmail.com>
Date: 2 Aug 2006 15:07:46 -0700
Message-ID: <1154556466.577423.185270@m79g2000cwm.googlegroups.com>

DA Morgan wrote:
>
> I can think of at least 9 ways to write that query. The way you tell the
> difference between them is with EXPLAIN PLAN.
>
> Go to Morgan's Library at www.psoug.org and look up EXPLAIN PLAN. You
> will also see the nine different ways (just need to reverse the logic).
>

Thanks for the help. I googled a bit for 'explain plan' and saw the following output to the query : SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT

|   0 | SELECT STATEMENT     |             |       |       |       |
|   1 |  TABLE ACCESS FULL   | DUAL        |       |       |       |
--------------------------------------------------------------------

Note: rule based optimization

9 rows selected.

I just couldn't make out anything from that output; a steep learning curve seems to be looming ahead.

Besides I mostly use TOAD and apparently it uses some other approach to 'explain plan'. Still, the exercise has been useful to me. Received on Wed Aug 02 2006 - 17:07:46 CDT