A C programmer's view of a relational database

The AGS Distributed Control System (AGSDCS) uses a relational database (Interbase) for the storage of all data on the host system network. This includes the static data which describes the components of the accelerator complex, as well as data for application-program setup and data records that are used in analysis. By creating a mapping of each relation in the database to a C record and providing general tools for relation (record) access, all the data in the database is available in a natural fashion to all the C programs on any of the nodes of the control system. In this paper the correspondence between the Interbase relations and the C structure is detailed with examples of C 'typedefs' and relation definitions. It is also shown how the relations can be put into memory and linked (related) together when fast access is needed by programs. (orig.)