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From: Franck Routier <franck.routier@axege.com>
To: pgsql-performance@postgresql.org
Subject: Drawbacks of create index where is not null ?
Date: Wed, 10 Oct 2012 19:06:23 +0200
Message-ID: <5075AB0F.5030005@axege.com> (raw)

Hi,

I have pretty large tables, with columns that might never receive any 
data, or always receive data, based on the customer needs.
The index on these columns are really big, even if the column is never 
used, so I tend to add a "where col is not null" clause on those indexes.

What are the drawbacks of defining my index with a "where col is not 
null" clause ?

Franck

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