Set permissions on newly created databases with rules - sql

Question

I have a situation whereby an application we use has many databases used for storage, and creates new ones on the fly as needed (SQL Server 2008 R2).
ApplicationDatabase
ApplicationDatabase_Storage001
ApplicationDatabase_Storage002
ApplicationDatabase_Storage003
etc...
As needed the application will create a new storage database for itself.
My problem is that I have a sql server account that is used for the ApplicationDatabase, and I want to automatically give it permissions to the storage databases as they are created, but not to any other database that happens to be created in the same sql server instance. I have no control over the creation of the storage databases.
I read In the answer to this question that I can add the account in the model database however this appears to add the permissions for all new databases, when I only want it to apply to the databases mentioned above.
The best solution I could come up with is a SQL server job or external app that runs once a day or so and looks for the existence of each database, applying the permissions on each that it finds, but this does not seem ideal.

Answer 1

You can implement a DDL trigger that will be fired whenever a new database is created. Depending on the properties of the database, like name or storage definition, you can probably run additional scripts on the new database to set up the required security.
http://msdn.microsoft.com/en-us/library/ms186406.aspx
Here's a snippet from the article above:
IF EXISTS (SELECT * FROM sys.server_triggers
WHERE name = 'ddl_trig_database')
DROP TRIGGER ddl_trig_database
ON ALL SERVER;
GO
CREATE TRIGGER ddl_trig_database
ON ALL SERVER
FOR CREATE_DATABASE
AS
PRINT 'Database Created.'
SELECT EVENTDATA().value('(/EVENT_INSTANCE/TSQLCommand/CommandText)[1]','nvarchar(max)')
GO
DROP TRIGGER ddl_trig_database
ON ALL SERVER;
GO
Regards
Piotr