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Posted by Andy Brown on 10 January 2020
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The new CREATE OR ALTER command in SQL
Another in a series of confessions! Did you know (we didn't!) that from SQL Server 2016 onwards you can choose to create or alter a procedure, function, trigger or view?
CREATE OR ALTER PROC spShowFilms
AS
-- list out all the films
SELECT
*
FROM
Film
The benefit of this is that it avoids a problem familiar to all SQL developers, which is what happens when you try to create a procedure or other object which already exists. So for example the first time that you run the following code:
-- create a new procedure
CREATE PROC spShinyNewProcedure
AS
-- do something amazing
SELECT * FROM Film
You get this:
The procedure has been created.
If you then press F5 to run the same code again, you get this:
The procedure already exists - you need to change CREATE to read ALTER to choose to make changes to the procedure.
The CREATE OR ALTER command gets round this problem, at the expense of some extra typing.