INFRA Database Design - Application Manager View

Finally, we get to the person who is supervising the overall application development effort. While this person has an interest in the other views, she/he has a particular interest in the work of the developers and the various versions or releases of the application system and its underlying application database(s).

Application System

This represents the product of the developers’ hard work, the actual application modules that show the screens that the users want and need to see. It includes both front-end modules that the users see, and the back-end modules that process the user input and prepare the user output. It can include the actual code behind those services that are being custom coded. It also includes code to talk to the various services whether custom written or not, and to the Application Databases.

Application Version

This may also be called an Application Release. It represents a frozen in time set of code for the modules in the Application System, often numbered according to local standards. For instance, release 1.0 might be the initial release of a system, while 1.2 is the second minor enhancement release. Application Versions are also often identified with a “tag” or “label” in the source control system. Task and Bug management software like JIRA often also have a place to record versions or releases. One goal of INFRA is to be able to coordinate its database with those of various Task Management and/or source control systems.

Application Database

This represents the various database structures and objects that contain and organize data used by one or more Application Systems. It may also include database procedural code like triggers. While an Application System can use objects in more than one Application Database and an Application Database can be used by more than one Application System, as a general rule, the relationship is one database to one application, especially for which application may update the database. Nonetheless, I have designed INFRA to be able to handle the less common many to many situation.

Database Version

This may also be called a Database Release. It represents a frozen in time set of objects in the Application Database, often numbered according to local standards. For instance, release 1.0 might be the initial release of a database, while 1.2 is the second minor enhancement release. It is usual to coordinate the database version numbers with the application version numbers – so that version 2.5 of the application goes with version 2.5 of its database. Even if you don’t do this, it is very important to make sure which version of the application matches which version of the database. Database Versions are also often identified with a “tag” or “label” in the source control system.

Entity Relationship Diagram for Application Manager View

This concludes my series on the database design for INFRA.  I am very interested in what you think of INFRA so far.  What did I get right?  What did I get wrong?  Where would you go from here?  Next time, I'll talk about implementation options.