Open Data Access Application Data Access for ClearPath OS 2200

Application Data Access for ClearPath OS 2200 enables OS 2200 programs to access remote data sources using the ActiveX Data Objects (ADO) connection mechanism. Using Application Data Access, OS 2200 programs can access a variety of data sources including SQL Server, Oracle and Microsoft Access databases and Microsoft Excel spreadsheets. OS 2200 programs can also access Enterprise Network Database Server and Enterprise Relational Database Server databases residing on other ClearPath enterprise servers.

Application Data Access provides a simple mechanism for programs to access network databases. OS 2200 applications don't need to know the structure of the data or its location. Nor do programmers need knowledge of SQL to use Application Data Access.

Application Data Access consists of these components:

• Agent
• Adapter
• Data Sources Utility

The Agent provides the application programming interfaces (API) for the OS 2200 programs. The APIs in Application Data Access are procedural wrappers to ActiveX Data Objects (ADO) data objects. Application programs (C and COBOL) running on the OS 2200 node of a ClearPath enterprise server use these APIs to access data sources through the Windows node.

The Adapter is the interface to the ActiveX Data Objects (ADO) data objects. It's a multiple-thread program and establishes an object for each open Application Data Access connection session. The ADO connection object maps to a thread. The Adapter runs on the Windows node of a ClearPath enterprise server. The Agent and Adapter use Messaging Integration Services for ClearPath OS 2200 to exchange data.

The Data Sources Utility (DSU) provides a centralized definition of the connections and their recordsets. Administrators use this utility to define the Application Data Access connection and its recordsets. During the definition, the utility uses ADO to verify each new connection and recordset. It also verifies a connection or recordset if its definition changes. PROCs are generated for use in COBOL, C and ASCII COBOL applications.