Do it like this:
SET DATEFIRST 1 -- Define beginning of week as Monday
SELECT [...]
AND WorkDate >= dateadd(day, 1-datepart(dw, getdate()), CONVERT(date,getdate()))
AND WorkDate < dateadd(day, 8-datepart(dw, getdate()), CONVERT(date,getdate()))
Explanation:
datepart(dw, getdate())
will return the number of the day in the current week, from 1 to 7, starting with whatever you specified using SET DATEFIRST.dateadd(day, 1-datepart(dw, getdate()), getdate())
subtracts the necessary number of days to reach the beginning of the current weekCONVERT(date,getdate())
is used to remove the time portion of GETDATE(), because you want data beginning at midnight.