The Relativity Database Management System (DBMS) connects Windows client-based tool products to COBOL data files. It processes SQL requests from the ODBC-enabled application (or tool) and performs the necessary actions to respond to the request with data obtained from the COBOL data files.
The Relativity DBMS comes in two variants: single-tier and a client/server. The single-tier product is named the Relativity Data Manager. The client/server product is named the Relativity Data Client and Relativity Data Server.
The Relativity Data Manager is a single-tier version of the Relativity DBMS. By single-tier, we mean that the product is installed on a single machine. In this configuration, the COBOL data files are installed on the same machine as the ODBC-enabled application and the Relativity Data Manager.
The Relativity Data Client and Relativity Data Server are a client/server version of the Relativity DBMS. In this configuration, the COBOL data files are typically not on the same machine as the ODBC-enabled application. In this case, the Relativity Data Client is installed on the same machine as the ODBC-enabled application, and the Relativity Data Server is installed on the same machine as the COBOL data files. The Data Server needs to be installed only once and on only the server machine, that is, the machine with the COBOL data files. The Data Client needs to be installed on each client machine that needs access to the data on the server machine. The Data Client sends the SQL requests from the ODBC-enabled application to the Data Server, which then processes the requests and returns only the resulting rows to the Data Client, which in turn returns them to the ODBC-enabled application.