Question

I am trying to check if a coupon is valid between two given dates.
I don’t have much SQL experience but currently the code is using BETWEEN to try to validate and the issue I am running into is that the endDate expires at midnight of day before (ex.10/12/2012 00:00:00.000 evaluates to midnight of 10/11) and I need it to extend through the midnight of 10/12.
So I am wondering if appending/adding 23:59:59 to the end date is the best way of performing this evaluation?

Currently Using:

ca.CreateDate between co.StartDate and co.EndDate 

Answer 1

Don’t use BETWEEN for continuously varying values.

You need…

    ca.CreateDate >= co.StartDate
AND ca.CreateDate <  co.EndDate

But you also need to add one day to your end date values. Either in the code (co.EndDate + 1 or similar), or in the data it self.

For example, if you want all times for the 1st week of 2012…

WHERE
      theDateTime >= '01 Jan 2012'
  AND theDateTime <  '08 Jan 2012'

This even applies to other levels of granularity.

-- First 12 hours of the day
WHERE
      theDateTime >= '01 Jan 2012 00:00'
  AND theDateTime <  '01 Jan 2012 12:00'

-- All of Jan
WHERE
      theDateTime >= '01 Jan 2012'
  AND theDateTime <  '01 Feb 2012'