Relational Databases

Relational databases are the standard. They are the most widely used type of database and one of the simplest models conceptually. A relational database management system (RDBMS) stores and relates data in tables (that is, rows and columns). Databases are simply warehouses of data. Each individual table in the database represents an abstract data type or some logical structure. The individual table cells contain the actual data itself. Each row constitutes a record in the database. Records are frequently linked to other records in other tables. Just as a Java object contains references to other objects, the same is true of records and their relationships with each other. Relating data in this way allows for fast and efficient data retrieval.

The RDBMS performs the data-retrieval operations, alleviating the need for the developer to write any code to manage or fetch the data. The use of a database essentially allows the developer to focus on the logical design of the data (and the game code) without having to worry about how the data is accessed and persisted. This level of abstraction comes at a price, though. Relational databases often, but not always, require a significant amount of overhead to run smoothly, and this can be a deterrent. It just depends on the project whether a database is warranted and how well it can fit into the system. Later we’ll look at the questions that must be asked to determine whether it makes more sense to use a relational database or some other form of customized data access.