Separar linhas em colunas postgresql

CREATE OR REPLACE FUNCTION public.func_dados_serra (
)
RETURNS void AS
$body$
DECLARE 
r						    RECORD;
p							RECORD;
q							RECORD;
qtd_aux						integer;
cabecalho	 				text;
linha						text;
BEGIN 
   
    cabecalho = 'MAQUINA';    
	
	FOR r IN SELECT data FROM dados_serra GROUP BY data ORDER BY data ASC
	LOOP
	cabecalho = cabecalho || ' | ' || r.data;         
	END LOOP;   
    
    RAISE NOTICE '%',cabecalho;
    
     FOR p IN SELECT maquina FROM dados_serra GROUP BY maquina
     LOOP   
        linha = p.maquina;
		
        FOR q IN SELECT qtd FROM dados_serra WHERE maquina = p.maquina ORDER BY data ASC        
        LOOP 
         linha = linha || ' | ' || q.qtd;
        END LOOP;
        
        RAISE NOTICE '%',linha;
     END LOOP;
END;
$body$
LANGUAGE 'plpgsql'
VOLATILE
CALLED ON NULL INPUT
SECURITY INVOKER
COST 100;

NOTICE:  MAQUINA | 2014-07-01 | 2014-07-02
NOTICE:  serra 1 | 12 | 14
NOTICE:  serra 2 | 18 | 15
Total query runtime: 33 ms.
1 row retrieved.

SELECT 250/4; 

SELECT 250/60; 

select (250/60) as hora, (250.0/60.0) - (250/60) as minutos;

select pa.ds_parada, coalesce(cast( (sum(ap.qtd_minutoparado)/60) as varchar),'') || (':') || 
coalesce(cast(trunc(((sum(ap.qtd_minutoparado)/60.0 - (sum(ap.qtd_minutoparado)/60))*60)) as varchar), '') as horas, sum(ap.qtd_minutoparado) as minutos
from apontador ap
inner join paradas pa on pa.seq = ap.cd_parada
where ap.cd_horas = 11 and ap.dt_apontador between '01/07/2014' and '08/07/2014' 
group by pa.ds_parada
order by minutos desc