Select * from tableA inpt, tableB ptbs
where inpt.z='A'
AND (inpt.pid    = ptbs.pid
     AND  inpt.instcd = ptbs.instcd);

Select * from tableA inpt, tableB ptbs
where inpt.z='A'
AND inpt.pid    = ptbs.pid
     AND  inpt.instcd = ptbs.instcd