The OpenEdge SQL Engine is designed to support software requirements for deployed applications. OpenEdge implements the SQL interface in a client/server configuration. OpenEdge SQL Access consists of:
An SQL database engine
A client application accessing the database through two available interfaces:
A JDBC API
An ODBC API
Because the SQL interface works through a client/server connection, it is integrated with the OpenEdge client/server architecture. Advanced Business Language (ABL), created and developed by Progress Software Corporation, is the programming language used to develop OpenEdge applications.
The following figure illustrates the architecture of the ABL and OpenEdge SQL clients when connected to the database in a client/server configuration.
Figure 1. Client/server architecture
In this configuration:
Both SQL servers and ABL servers are able to connect with the OpenEdge database.
The SQL server integrates with OpenEdge processes and the Admin Service through which it can be started.
The SQL server processes always perform database operations through the shared memory attached to the database. The shared memory is common to all processes running against a specific OpenEdge database.
The SQL database servers are only accessible from SQL clients. The connection is always established through the network layer from the SQL clients.
Note: The multiple volumes, located on the right side of the above figure, symbolize the fact that the database is multi-volume.
An SQL database engine
