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From Andy Jefferson <li...@datanucleus.org>
Subject Re: DatabaseMetaData.getIndexInfo() to get unique compound indexes
Date Tue, 28 Jun 2011 15:35:10 GMT
> I believe that you see this behavior because the unique constraint does
> not give rise to a unique index. The index forbids duplicates if all of
> the key values are non-null. However, if any of the key values are null,
> then duplicates are allowed. If you need an index which forbids
> duplicate nulls,  then you can use the CREATE INDEX statement.

Thanks Rick, that works much better :-)

-- 
Andy

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