Código:
SELECT U.idufb,U.dinero,U.gasolina,U.idclubes,count(PXU.idufb) numprop FROM user U LEFT JOIN propertysxusers PXU ON U.idufb=PXU.idufb WHERE U.idufb IN(".$id_frieds.") GROUP BY U.nick;"
pero me tira el siguiente error : ERROR: column "u.idufb" must appear in the GROUP BY clause or be used in an aggregate function at character 8.
saludos