Entity Framework Code First

The code first approach, part of the Entity Framework 4.1, was the last workflow Microsoft introduced. It lets you transform your coded classes into a database application, with no visual model used. Of the three workflows, this approach offers the most control over the final appearance of the application code and the resulting database. However, it’s also the most work. And it presents the biggest obstacles to communicating well with non-developers during the initial design process.

With the code first workflow, you also need to write glue code in the form of mapping and, optionally, database configuration code. However, even in this respect, the workflow provides developers with significant advantages in flexibility. You know precisely what is going on with the underlying code at all times, which is a huge advantage when working with enterprise systems. The cost of this knowledge is equally huge; it takes considerably longer to develop the application.

A code first workflow is the only realistic solution when an organization decides on a code focus approach for an existing database. However, in this case, the developer must do the reverse engineering of the database and create classes that reflect the database design as it exists. Microsoft does provide some assistance to the developer to perform this task in the form of the Entity Framework Power Tools, but you should expect to still end up tweaking the code to precisely match the application requirements and the underlying database.