select distinct a.osuser, a.username, b.no_usuario, c.sg_unidade_org, a.program
from admin.tb_after_logon a, dbseguranca.tb_usuario b, dbsistru.tb_unidade_org c
where upper(a.osuser) = b.co_username (+)
and   b.co_interno_uorg = c.co_seq_interno_uorg (+)
and   a.logon_time > '15-MAR-08' order by 1

/* select * from admin.tb_after_logon WHERE logon_time > '15-MAR-08' ORDER BY LOGON_TIME DESC */