Patterns of Enterprise Application Architecture

Chapter 2. Organizing Domain Logic

In organizing domain logic I’ve separated it into three primary patterns: Transaction Script (110), Domain Model (116), and Table Module (125).

The simplest approach to storing domain logic is the Transaction Script (110). A Transaction Script (110) is essentially a procedure that takes the input from the presentation, processes it with validations and calculations, stores data in the database, and invokes any operations from other systems. It then replies with more data to the presentation, perhaps doing more calculation to help organize and format the reply. The fundamental organization is of a single procedure for each action that a user might want to do. Hence, we can think of this pattern as being a script ...