Grouping sets by year, month, and date

Question

Is it possible to collapse the date, month and year with GROUPING SETS, where the dates are displayed and grouped by month and year, and instead of the month null, the value of the month and year is displayed?

Here is sample data and my attempt to use grouping sets

create table #tbl_data
(
employeeId int
,productLine int
,salesDate datetime
,salesTotal money
)

insert into #tbl_data
values
(1,1,'02/09/2017',199)
,(1,1,'04/10/2017',379)
,(2,1,'04/21/2017',323)
,(2,1,'04/10/2017',461)
,(2,1,'06/11/2017',304)
,(3,1,'01/28/2017',147)
,(3,1,'02/09/2017',320)
,(4,1,'03/07/2017',344)
,(4,1,'03/13/2017',176)

select
    productLine, 
    employeeId, 
    salesDate, 
    mon=month(salesdate),
    yr=year(salesdate), 
    sum(salesTotal) as salesTotal
from 
    #tbl_data

group by grouping sets
(
    (productLine, employeeId, salesDate)
    ,(productLine, employeeId)
    ,(productLine)
)

This is what the request returned (left) and what I wanted to fulfill (right)

Answer 1

You can use:

;WITH cte AS (
  select
    productLine, 
    employeeId, 
    salesDate, 
    mon=month(salesdate),
    yr=year(salesdate),
    salesTotal
  from #tbl_data   
)
select
    productLine, 
    employeeId, 
    salesDate, 
    mon,
    yr ,
    sum(salesTotal) as salesTotal
from cte
group by grouping sets
(
     (productLine, employeeId, salesDate, yr)
    ,(productLine, employeeId, yr)
    ,(productLine)
    ,(productLine, mon, yr)
);

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