Modify User-defined Functions

You can modify user-defined functions in SQL Server 2016 by using SQL Server Management Studio or Transact-SQL. Modifying user-defined functions as described below will not change the functions’ permissions, nor will it affect any dependent functions, stored procedures, or triggers.

Limitations and Restrictions

ALTER FUNCTION cannot be used to perform any of the following actions:

• Change a scalar-valued function to a table-valued function, or vice versa.
• Change an inline function to a multistatement function, or vice versa.
• Change a Transact-SQL function to a CLR function, or vice-versa.

Alters an existing Transact-SQL or CLR function that was previously created by executing the CREATE FUNCTION statement, without changing permissions and without affecting any dependent functions, stored procedures, or triggers.