A lot of beginner developer are facing this issue in IT industry, that how to Drop the user define function from database if it exists.
It is always good practice to write the drop statement before creating any stored procedure or the database function.You should always preferred the Object_id method, it seems simpler to read in the code. Always curious why the Microsoft generated sample code uses the sys.objects lookup instead.
Drop the user define function from database if it exists.
Below script will help to drop the scalar function present in SQL Server if exist. Lets say the function name is fn_GetFirstDayOfWeek
IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[fn_GetFirstDayOfWeek]')
AND type in (N'FN', N'IF',N'TF', N'FS', N'FT'))
DROP FUNCTION [dbo].[fn_GetFirstDayOfWeek]