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From Katherine Marsden <kmarsdende...@sbcglobal.net>
Subject Are these ROW_NUMBER caveats still true?
Date Thu, 07 Mar 2013 17:03:07 GMT
http://db.apache.org/derby/docs/10.9/ref/rreffuncrownumber.html

  * Derby does not currently allow the named or unnamed window
    specification to be specified in the OVER() clause, but requires an
    empty parenthesis. This means the function is evaluated over the
    entire result set.
  * The ROW_NUMBER function cannot currently be used in a WHERE clause.
  * Derby does not currently support ORDER BY in subqueries, so there is
    currently no way to guarantee the order of rows in the SELECT
    subquery. An optimizer override can be used to force the optimizer
    to use an index ordered on the desired column(s) if ordering is a
    firm requirement.


I see these possibly relevant fixes:

https://issues.apache.org/jira/browse/DERBY-3634
https://issues.apache.org/jira/browse/DERBY-4397

Also are there still performance considerations with ROW_NUMBER?
I see:
https://issues.apache.org/jira/browse/DERBY-3505

Are there still other concerns with ROW_NUMBER?

Thanks

Kathey

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