1) One language and one system: SQL on a database that will last much more than the applications 2) SQL has a limited scope, and so do SQL tools. You need advan

1) One language and one system: SQL on a database that will last much more than the applications 2) SQL has a limited scope, and so do SQL tools. You need advanced tools if you have "app code": it's a necessary evil. 3) At worst, you can write unit tests for app code that calls SQL queries and stored procedures. 4) "Usually" isn't enough, moving logic to the client requires moving data to the client.