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>
> General clues:
>
> The predicates you supplied can be propagated
> and moved by transitive closure, but I can't tell
> whether that's relevant because you have to look
> at the dbms_xplan() output to see what predicates
> Oracle is using. Note particularly that your join
> predicate CAN disappear, or be supplemented by
> an extra constant predicate.
>
Jonathan,
I appreciate you taking a look at this, thanks.
I think you've hit the nail on the head.... When you mentioned transitive closure you got me thinking.
I first tried running the query with a join condition which differed from the filter condition. This pushed the filters down into the table.
So I now have a workaround which is to add a ||'' (i.e. a null string) to the end of each joined column.
This fixes the issue (as a workaround).
I'm still waiting for Oracle support to tell me whether this is a bug or a 'feature'.
Thanks very much for your time.
Matt Received on Wed Aug 23 2006 - 12:01:06 CDT