Postgres Function End Loop and return Error

Question

I have tried to create this function but the system is returning a \"LOOP error\" and I don\'t know how to return 3 variables at the same time. I\'ve tried hard to figure this o

Answer 1

Use OUT parameters to return a single row with multiple columns. The RETURN type is optional in this case, I quote the manual here:

When there are OUT or INOUT parameters, the RETURNS clause can be omitted.

CREATE OR REPLACE FUNCTION conta_relatos(
    _fator_normativo integer
   ,_fator_determinativo integer
   ,OUT rel_pri integer
   ,OUT rel_sec integer
   ,OUT rel_ref integer
   ) AS
$func$
DECLARE
   tipo_relato text;
BEGIN

rel_pri := 0;
rel_sec := 0;
rel_ref := 0;

FOR tipo_relato IN
   SELECT f."Tipo_Relato"
   FROM   "Vinculos" v
   JOIN   "Fontes"   f ON f."ID" = v."Item"
   WHERE  v."Fator_Normativo" = _fator_normativo
   AND    v."Fator_Determinativo" = _fator_determinativo
LOOP
   CASE tipo_relato
   WHEN '1 - Relato Primário' THEN 
      rel_pri := rel_pri + 1;
   WHEN '2 - Relato Secundário' THEN 
      rel_sec := rel_sec + 1;
   WHEN '3 - Relato Referencial' THEN 
      rel_ref := rel_ref + 1;
   END CASE;
END LOOP;

-- No RETURN needed, OUT parameters are returned automatically.

END
$func$ LANGUAGE plpgsql;

Call:

SELECT * FROM conta_relatos(1,2);

I also largely simplified your function. Among others:

• Use "Simple CASE" for your assignments.
• Simplify two queries into one with a join.

The whole function could easily be rewritten as a single SQL statement.