Ver originalselect t1.num as servicio, t2.nombre as instalador1,t3.nombre as instalador2,t4.nombre as instalador3from mservicios T1inner join instaladores T2 on T2.id = T1.id1inner join instaladores T3 on T3.id = T1.id2inner join instaladores T4 on T4.id = T1.id3