Re: why ?????????

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

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The Co-operative Oracle Users' FAQ
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• 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'
  >
  

>
>
>
> >>> oramagic_at_hotmail.com 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: jonathan_at_jlcomp.demon.co.uk

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