Horton

unique constraint with significant nulls?

Mike Blackwell <mike.blackwell@rrd.com>

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From: Mike Blackwell <mike.blackwell@rrd.com>
To: pgsql-general <pgsql-general@postgresql.org>
Date: 2012-09-25T15:05:15Z
Lists: pgsql-general 
How would one go about building a multi-column unique constraint where null
is a significant value, eg. (1, NULL) <> (2, NULL)?

I see a number of references to not being able to use an index for this,
but no mention of an alternative.  Any pointers would be appreciated

__________________________________________________________________________________
*Mike Blackwell | Technical Analyst, Distribution Services/Rollout
Management | RR Donnelley*
1750 Wallace Ave | St Charles, IL 60174-3401
Office: 630.313.7818
Mike.Blackwell@rrd.com
http://www.rrdonnelley.com


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* <Mike.Blackwell@rrd.com>*