Personal Tech Journal

To delete a function we need to use the drop function The Syntax is as follows DROP FUNCTION < FunctionName > The below shows how to drop a function DROP FUNCTION USFORMATPHONE

We can modify the user defined functions by using the Alter command. The Syntax as shown below Scalar-valued Functions ALTER FUNCTION [ schema_name. ] function_name ( [ { @parameter_name [ AS ][ type_schema_name. ] parameter_data_type     [ = default ] }     [ ,...n ]   ] ) RETURNS return_data_type     [ WITH [ ,...n ] ]     [ AS ]     BEGIN         function_body         RETURN scalar_expression     END [ ; ] Table-valued Functions ALTER FUNCTION [ schema_name. ] function_name ( [ { @parameter_name [ AS ] [ type_schema_name. ] parameter_data_type     [ = default ] }     [ ,...n ]   ] ) RETURNS @return_variable TABLE     [ WITH [ ,...n ] ]     [ AS ]     BEGIN         function_body         RETURN     END [ ; ] The below shows how a function has been modified to change the message ALTER FUNCTION USFORMATPHONE(@PhoneNumber varchar(25)) RETURNS Varchar(50) AS BEGIN DECLARE @phone varchar(50) IF(LEN(@PhoneNumber) = 10) SET @phone = '('+ SUBSTRING(@PhoneNumber,1,3) + ')&#