variables in procedures

How can I distinguish between the name and the value of a variable?

Example:

CREATE FUNCTION test(VARCHAR) RETURNS INTEGER AS '

DECLARE
col1 ALIAS FOR $1
BEGIN
select col1 from tab where col1=´´col1´´;
END;
´ LANGUAGE 'plpgsql';

Is my doubt understood?

--
Porqué usar una base de datos relacional cualquiera,
si podés usar PostgreSQL?
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Martín Marqués | mmarques(at)unl(dot)edu(dot)ar
Programador, Administrador, DBA | Centro de Telematica
Universidad Nacional
del Litoral
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