Try this;
select oh_name as Parent
, isnull(jpp_alias, jpp_object) as Task
, jpp_lnr as TaskNumber
, JPP_ErlstStTime EarliestStartTime
from jpp, oh
where not jpp_erlststtime is null
and oh_idnr = jpp_oh_idnr and not oh_otype = 'JSCH'
and oh_client = 100
order by 1, 2, 3
(wrote this for SQLServer, AE V11.2.1)