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From John English <john.fore...@gmail.com>
Subject Re: Unique constraint, or something like it
Date Mon, 12 Mar 2012 16:52:16 GMT
On 12/03/2012 15:04, Knut Anders Hatlen wrote:
> Please file a bug report so that we can fix the manual. Derby has
> supported UNIQUE constraints on nullable columns since 10.4.

Oops -- I was looking at an old copy of the manual!

> Derby also has unique indexes that, in contrast to unique constraints,
> consider two null values duplicates:
>    CREATE UNIQUE INDEX FOO_3 ON foo(section,title)

But that won't actually prevent me entering duplicate values with a null
section value, will it?

  John English | My old University of Brighton home page is still here:
               | http://www.cem.brighton.ac.uk/staff/je/

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