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Date: Sun, 31 Jan 2010 03:26:14 +0100
From: Andreas <maps.on@gmx.net>
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To: pgsql-sql@postgresql.org
Subject: Howto have a unique restraint on UPPER (textfield)
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Hi,

is there a way to define a unique restraint on UPPER (textfield)?

E.g.  
mytable (
    name_id serial PRIMARY KEY,
    name varchar(255),
    UNIQUE ( upper (name) )
)

psql throws a syntax error because of the upper() function.

I need to prohibit that  2 of strings like   cow, Cow, CoW  appears in 
the name-column.