Ken Williamson

Using The Active Record Pattern With SQLite and C++

The Active Record Pattern is a popular design pattern for accessing data stored in a relational database. This pattern can be used to greatly simplify the use of SQLite in C++ applications. The concept of the Active Record Pattern is to use an object to wrap a row of data in the database. For an example, I will use the Section table from DocUMentDS, my recently released Desktop Document Manage System. Figure 1 show the UML for DocUMentDS.

The Section table has the following fields

1. id (int)
2. name (varchar)
3. user_id (int) (foreign key)

One of the main concepts of the Active Record Pattern is the containment of all data access methods and business logic inside the corresponding class. For example, Figure 2 show the simplified generic UML of the actual Section class:

Notice that the class contains accessors and mutator for the class attributes, but also contains business methods save, update, remove and finders for this class. The Active Record Pattern allows us to simplify data access by placing all the needed methods inside the Section class. Therefore, the Section object contains everything we need to create, access or modify a Section objects.

This shows the code for section.h:

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