SQL WHERE timestamp BETWEEN MIDNIGHT AND MIDNIGHT

Question

For my website I must select all messages sent between midnight (the previous night) and midnight (the next night). Basically, it's a 24 hours range.

I don't know how to do that as I store the date in a timestamp format in my DB.For example, last message was posted on 2013-10-18 11:23:35.

What I want is all message posted between 2013-10-18 00:00:00 and 2013-10-18 23:59:59. Is that possible, if yes, how could I do that ?

Answer 1

You can calculate the required time in T-SQL as :

-- for previous day mid night  as start time
declare @start_datetime datetime,@end_datetime datetime 
Select @start_datetime = DATEADD(d,0,DATEDIFF(d,0,GETDATE()))
-- for current day mid night as end time
Select @end_datetime = DATEADD(SS,86399,DATEDIFF(d,0,GETDATE()))

select @start_datetime, @end_datetime

and then use you column name to check whether it exists between these two values.

Answer 2

To find out what happened between DatetimeA and DatetimeB, the sql keyword between is not your friend. It generally causes one to miss records. This construct is better.

where YourDateTimeField >= StartDateTime
and YourDateTimeField < JustAfterTheEndDateTime

In your case, you can simplify it with

where YourDateTimeField >= DateA
and YourDateTimeField < TheDayAfterDateA