Date: Mon, 13 Jun 2011 20:04:54 +0100
From: Tarlika Elisabeth Schmitz <postgresql4@numerixtechnology.de>
To: pgsql-sql@postgresql.org
Subject: extract some column/value pairs via hstore
Message-ID: <20110613200454.2a903880@dick.coachhouse>
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In a PL/pgSQL function, I need to extract column/value pairs from a
table ignoring some of the columns.
The excluded column names have previously been stored in an array
"ak", which contains

array['country_fk', 'region_fk', 'id']

SELECT key, value FROM 
(
    SELECT (each(hstore(town))).* FROM town 
) AS nk
WHERE key NOT IN (SELECT unnest(ak));

=====

The above statement produces the desired result but it seems a bit
convoluted. Can this be done in a more elegant way?

=====
PostgreSQL 8.4

example: 
CREATE TABLE town
(
  country_fk character varying(3) NOT NULL,
  region_fk character varying(3) NOT NULL,
  id serial NOT NULL,
  "name" character varying(50) NOT NULL,
  source character varying(2) NOT NULL
)

-- 

Best Regards,
Tarlika Elisabeth Schmitz