在WHERE子句中带有日期的CASE语句

Question

I am trying to write a WHERE clause to look back 3 days when the day of the week is Monday by joining in the calendar table.

WHERE        
CASE WHEN calendar.DW = 2 Then (date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-3))
            AND GETDATE() ELSE
        date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-1))
            AND GETDATE()
            END

I am getting an error on the "BETWEEN" operator for the above. Is it possible to do what I am attempting, or am I going about this in the wrong manner?

Thanks for the help.

Answer 1

You need to add a condition which can be evaluated to true or false , like so:

WHERE        
(CASE WHEN calendar.DW = 2 AND date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-3))
            AND GETDATE() THEN 1 WHEN
        date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-1))
            AND GETDATE() THEN 1 ELSE 0
            END) = 1

Answer 2

You could try a simple where clause:

WHERE calendar.DW = 2 AND 
      date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-3)
            AND GETDATE() 
      OR
      date_created BETWEEN DATEADD(hour,8,DATEDIFF(d,0,GETDATE()-1))
            AND GETDATE()