Select p.prempl, p.txqtr ;
from a_prehtx pre, LEFT JOIN  a_prehtx p ON pre.prempl = p.prempl ;
where p.txqtr = '3' And (pre.txqtr = '2' OR p.prempl NOT IN (SELECT prempl FROM a_preftx)) ;
  AND (p.qtax = 0 AND p.qbase = 0 AND p.qwage = 0) ;
  AND p.ybase<>(pre.Ybase+NVL(p.qbase,0));
  AND pre.taxid = p.taxid ;
group by p.prempl, p.txqtr into cursor curNeedUpdate2