SQL function and input variables - Mailing list pgsql-general

I was makeing an SQL function and got an error which on a sintax that
I thouhgt would work:

CREATE OR REPLACE FUNCTION dicInsertarPalabra(p TEXT)
RETURNS INT AS $body$
    INSERT INTO public.diccionario (palabra) VALUES (quote_literal(p));
    SELECT COALESCE(codigo,0) FROM public.diccionario
           WHERE palabra = quote_literal(p);
$body$ LANGUAGE 'SQL';

Changing p for $1 in the body of the function makes it work. But,
can't we label input arguments like how I did here?

--
Martín Marqués
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DBA, Programador, Administrador