Question

I’m using SqlServer for the first time, and in every single one of our create procedure scripts there is a block of code like below to remove the procedure if it already exists:

IF EXISTS (SELECT *            FROM information_schema.routines            WHERE routine_name = 'SomeProcedureName'            AND routine_type = 'PROCEDURE'  BEGIN     DROP PROCEDURE SomeProcedureName END //then the procedure definition 

To stop cutting and pasting this boilerplate code in every file I would like to put this code in its own stored procedure so that instead the scripts would look like this:

DropIfRequired('SomeProcedureName') //then the procedure definition 

My attempt at a solution is:

CREATE PROCEDURE DropIfRequired (     @procedureName varchar ) AS IF EXISTS (SELECT * FROM information_schema.routines             WHERE routine_name = @procedureName             AND routine_type = 'PROCEDURE')  BEGIN     DROP PROCEDURE @procedureName END 

But I then get the following error:

Msg 102, Level 15, State 1, Procedure DeleteProcedure, Line 10 Incorrect syntax near ‘@procedureName’.

Any ideas how to do what I want?

Answer 1

The full answer is:

 DECLARE @SQL VARCHAR(8000) SELECT @SQL = ‘USE ‘ + DB_NAME() + CHAR(10) SET @SQL = @SQL + ‘DROP PROCEDURE ‘ + @procName –PRINT @SQL EXEC(@SQL) 

The one given by Andrew will only work if the default database for your login is set to the database you want. When using dynamic sql you get a new database context. So if you do not have a default database set you will execute the command from master.