T-SQL Between Dates Confusion

Question

I am working with T-SQL in SQL Server 2000 and I have a table TRANSACTIONS which has a date column TRANDATE defined as DateTime, among many other c

Answer 1

As you have discovered, if you don't specify a time when entering a date, it defaults to midnight in the morning of the date. So 12/31/2010 stops at midnight when that day begins.

To get all dates for 12/31/2010, you can either specify the time, as you have done, or add one day to the ending date. Without a time, 1/1/2011 ends at the stroke of midnight on 12/31/2010. So, you could do BETWEEN 12/1/2010 AND 1/1/2011. You can use DATEADD to add the day in your SQL if that makes it easier.

There is some risk in that second approach of adding a day. You will get any records for 1/1/2011 that carry the time of 00:00:00.

Here's one way to perform the DATEADD:

DECLARE @FromDate datetime, @ToDate datetime
// These might be stored procedure input parameters
SET @FromDate = '12/1/2010'
SET @ToDate = '12/31/2010'

SET @ToDate = DATEADD(d, 1, @ToDate)

Then you use @ToDate in your WHERE clause in the BETWEEN phrase in the usual way.