-- # $Id$
-- # $HeadURL$
-- # $Author$

CREATE OR REPLACE FUNCTION exists_sequence(sequenceName text, dbSchema text) RETURNS bool AS
$$
DECLARE
   exist_sequence "char";
BEGIN

   EXECUTE 'SELECT c.relkind 
            FROM   pg_class     c
            JOIN   pg_namespace n ON n.oid = c.relnamespace
            WHERE  c.relname = $1
            AND    n.nspname = $2
            AND    c.relkind = ''S'''
   INTO exist_sequence
   USING sequenceName, dbSchema; 

   IF exist_sequence IS NOT NULL THEN
      RETURN TRUE;
   ELSE                    
      RETURN FALSE;
   END IF;

END;
$$
LANGUAGE plpgsql;