Suppose you’re given a date and asked to retrieve data for the whole week in which the given date falls. The example code produces the Week Start Date and Week End Date:
--Please set your appropriate values for @REPORT_DATE and @WEEK_BEGINING
DECLARE @REPORT_DATE DATETIME, @WEEK_BEGINING VARCHAR(10)
SELECT @REPORT_DATE = '2004-09-21T00:00:00'
SELECT @WEEK_BEGINING = 'MONDAY'
IF @WEEK_BEGINING = 'MONDAY'
SET DATEFIRST 1
ELSE IF @WEEK_BEGINING = 'TUESDAY'
SET DATEFIRST 2
ELSE IF @WEEK_BEGINING = 'WEDNESDAY'
SET DATEFIRST 3
ELSE IF @WEEK_BEGINING = 'THURSDAY'
SET DATEFIRST 4
ELSE IF @WEEK_BEGINING = 'FRIDAY'
SET DATEFIRST 5
ELSE IF @WEEK_BEGINING = 'SATURDAY'
SET DATEFIRST 6
ELSE IF @WEEK_BEGINING = 'SUNDAY'
SET DATEFIRST 7
DECLARE @WEEK_START_DATE DATETIME, @WEEK_END_DATE DATETIME
--GET THE WEEK START DATE
SELECT @WEEK_START_DATE = @REPORT_DATE - (DATEPART(DW, @REPORT_DATE) - 1)
--GET THE WEEK END DATE
SELECT @WEEK_END_DATE = @REPORT_DATE + (7 - DATEPART(DW, @REPORT_DATE))
PRINT 'Week Start: ' + CONVERT(VARCHAR, @WEEK_START_DATE)
PRINT 'Week End: ' + CONVERT(VARCHAR, @WEEK_END_DATE)
The above code produces the following result:
Week Start: Sep 20 2004 12:00AM — Which is Monday
Week End: Sep 26 2004 12:00AM — Which is Sunday