It's worth noting that even in the execution path
you get a clue that the table isn't actually visited:
Note the FILTER line -
FILTER means too many things, but one of the
meaning is:
"I'm not really going to do the child bit
because I know that the result set will
be empty"
This meaning appeared (I think) when partition
view were introduced to show partition elimination
Regards
Jonathan Lewis
http://www.jlcomp.demon.co.uk
The educated person is not the person
who can answer the questions, but the
person who can question the answers -- T. Schick Jr
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The Co-operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
----- Original Message -----
>
> select count(*) from crazy_table where 1=2
>
> Explain Plan
> ---------------------------------------------------------------
> ...4 SELECT STATEMENT
> ...3 .SORT (AGGREGATE)
> ...2 ..FILTER
> ...1 ...TABLE ACCESS (FULL) OF 'ARTHUR.CRAZY_TABLE'
>
>
>
>
> >>> [EMAIL PROTECTED] 04/03/03 05:58PM >>>
> If I execute a query like ,
> select count(*) from some_table where 1=2 .
> why does oracle bothers to look at tables . Since there is only one
> condition which is false .
>
--
Please see the official ORACLE-L FAQ: http://www.orafaq.net
--
Author: Jonathan Lewis
INET: [EMAIL PROTECTED]
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