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Archives of the TeradataForum
Message Posted: Wed, 29 Jan 2014 @ 20:14:02 GMT
| Subj: | | Re: Join Index created with ROWID is not used |
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| From: | | Pluebell, Fred |
Look at the EXPLAIN for the inner join with ROWID.
After Table B is joined to the JI, the spool must be redistributed by the ROWID for table A and joined to that table to pick up the other
columns.
In the case of Outer Join, the ROWID might be NULL for many rows - in which case processing would be very skewed. The optimizer isn't willing
to take that chance.
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