Extract workspace that there is no data entry more than one month

Question

I have a table Timesheet with these columns:

IDWORKSPACE | DTDATE | workeddays

And another table TWorkspace :

IDWORKSPACE | TYPE | NAME

How could I extract all workspace names that there is no entry data for worked days for more than one month?

Answer 1

the below code prints records in TWORKSPACE table if there is no record in TIMESHEET table matching with IDWORKSPACE

select * from tworkspace w
where not exists (
   select 1 from TIMESHEET t
   where w.IDWORKSPACE = t.IDWORKSPACE
   group by IDWORKSPACE
   having sum(workeddays) > 30
)

Answer 2

Please, check if this works:

select *
from TWorkspace
where IDWORKSPACE in(
    select IDWORDSPACE
    from Timesheet
    where DTDATE >= dateadd(mm, getdate(), -1)
)