SELECT 
x.nsql_level
, x.name
, x.start
, x.finish
, x.uid
, x.prwbssequence
, CASE WHEN x.nsql_level < 2 THEN x.uid ELSE NULL END hg_has_children
FROM
(
select 
1 nsql_level
, i.name name
, i.schedule_start start
, i.schedule_finish finish
, i.id UID
, 0 prwbssequence
from inv_investments i
where i.ID = 5184386
--where @where:param:user_def:string:hg_row_id@ is null
--and (@where:param:user_def:integer:param_project_id@ = i.id)
group by 
name
, i.schedule_start
, i.schedule_finish
, i.id

union
/* Level 2 - Program Key Milestones */
select 
2 nsql_level
, t.prname name
, t.prstart start
, t.prfinish finish
, t.prid UID
, t.prwbssequence
from prtask t
where t.prprojectid = 5184386

) x
order by 
x.nsql_level
, x.prwbssequence