SIMPLY QUERYING ACROSS TIME

A temporal relational database includes a relational database framework that allows for all the capabilities of a standard relational database with the addition of the concept of time. Transactions, which can be modifications of attribute values or changes to the database schema, can be stored with temporal histories. Through the use of these temporal histories, the temporal database is able to seamlessly respond to queries for times that are in the past, present, or future. Furthermore, transactions can be entered into the temporal relational database that are not effective until some point in the future, thus allowing for seamless migration of the data and schema of a database. Applications that access data in a temporal database may retrieve a time appropriate schema from the temporal database. An exemplary use of a temporal database to manage roles and responsibilities within an organization is described.