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Message Posted: Fri, 08 Feb 2002 @ 20:10:19 GMT


     
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Subj:   Re: optimiser query
 
From:   Michael Larkins

Hi All:

I do not have a system available to attempt this, but you might try it.

The inner join syntax can be written with either a WHERE clause to add residual condition(s) or a compound ON (as shown in the two examples below).

SEL tbla.col1
FROM tbla inner join tblb
ON tbla.join_col = tblb.join_col
WHERE tbla.IDX_col = 'My value';

versus

SEL tbla.col1
FROM tbla inner join tblb
ON tbla.join_col = tblb.join_col
AND tbla.IDX_col = 'My value';

Although the answer set is the same for both, it would be interesting to know for sure if this changes the join plan to use the index in a nested join instead of redistribution for a merge join.


Regards,

Mike



     
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