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
BEGINselect 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@unl.edu.ar
Programador, Administrador, DBA |       Centro de Telematica                      Universidad Nacional
        del Litoral
 
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