level 1
use tempdb
create table tb#(parentAGI nvarchar(50),timestarted datetime,timecompleted datetime)
insert into tb# values('A123456','2018-12-20 21:39:01','2018-12-20 22:39:01')
insert into tb# values('A123456','2018-12-20 18:39:01','2018-12-20 23:39:01')
--以上为测试数据
select parentAGI,SUM(DATEDIFF(MINUTE,timestarted,timecompleted))
from tb#
group by parentAGI
2018年12月22日 08点12分
