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From Knut Anders Hatlen <knut.hat...@oracle.com>
Subject Re: How Much Memory for hash joins
Date Thu, 28 Feb 2013 17:34:13 GMT
Mike Matrigali <mikem_app@sbcglobal.net> writes:

> I have always assumed that the intent of the option is per opened
> "table" in store.  This is not user friendly at all since user does
> not really know how this matches up to their query, which is likely
> why the option was never made public for a zero admin db.

There's a brief discussion in DERBY-4620 on how this setting could be

Also, the memory estimates we use for the hash tables are inaccurate
(they are too low), so maxMemoryPerTable is effectively higher than its
nominal value. There's a patch attached to the issue that fixes the
estimates, but I've been hesitant to check it in, since it changes a lot
of query plans in the regression tests (wisconsin & co).

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