SELECT tab1.datetime_start, tab1.datetime_end
, datediff("h",datetime_start,dateadd("h",17,cdate(format(datetime_start,"yyyy-mm-dd")))) as befor_5pm
, datediff("h",dateadd("h",8,cdate(format(datetime_end,"yyyy-mm-dd"))),datetime_end) AS after_8am
FROM tab1