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From Knut Anders Hatlen <knut.hat...@oracle.com>
Subject Re: Inconsistent SQLSyntaxErrorException (Hash join requires an optimizable equijoin predicate...)
Date Sun, 11 Jul 2010 15:30:02 GMT
Knut Anders Hatlen <knut.hatlen@oracle.com> writes:

> Another thing is that the ROW_NUMBER() implementation was more or less
> completely rewritten in Derby 10.6 to address some bugs, so perhaps 10.6
> would handle this query differently.

I managed to reproduce the bug on 10.5.3.0 by adding an optimizer
override that forced the use of a hash join. With 10.6.1.0 it looks like
the optimizer is able to construct a hash join for the query, and I
don't see the error any more. And a little more digging showed that the
query stopped failing when the ROW_NUMBER rewrite went into the codeline
(https://issues.apache.org/jira/browse/DERBY-3634).

So I think you should be able to get around this problem either by
upgrading or by adding the optimizer override suggested in the previous
mail to force a nested loop join.

-- 
Knut Anders

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