Best approach to remove time part of datetime in SQL Server

Question

Which method provides the best performance when removing the time portion from a datetime field in SQL Server?

a) select DATEADD(dd, DATEDIFF(dd, 0, getdate(         


        

Answer 1

Strip time on inserts/updates in the first place. As for on-the-fly conversion, nothing can beat a user-defined function maintanability-wise:

select date_only(dd)

The implementation of date_only can be anything you like - now it's abstracted away and calling code is much much cleaner.