TPF Application Requester
The TPF Application Requester (TPFAR) is a separately priced feature of TPF 4.1 which supports IBM's DRDA architecture as a client. DRDA implements the remote unit of work method of distributed access which allows working with data located on remote systems.
This allows a TPF application using SQL commands to have direct access and update capability to data residing on a remote DRDA compliant database, such as but not limited to DB2 on OS/390, OS/2, AIX, or Windows NT. TPFAR implements the application requester (AR) portion of the database management system and does not include server support.
The remote database must implement the application server (AS) function which facilitates the TPFAR connection rising TPFAR. To use this feature SQL commands are imbedded in TPF applications code. The application must be precompiled. The application is processed by the OS/390 DB2 precompiler so that the SQL commands are removed from the application and replaced with system calls. During execution, TPFAR is passed control when the system calls are made and routes the requests to the applications server (AS) via LU6.2 or or TCP/IP protocols. Once the requests are processed by the application server (AS), the data is passed back to TPFAR returns control, along with any data to the TPF application. The application then regains control and continues processing.
TPFAR supports both dynamic and static SQL commands in addition to handling all of the necessary character set and numeric translation that may be required if the database resides on a server that is not using the same data formats as the TPF system.
To the process of loading applications that use SQL commands on TPF easier, TPFAR has implemented a process called "run-time bind", in which TPFAR creates a bind package for an application while it is running, instead of requiring that the bind package be created prior to program execution.
Product Advantages
- Complies with IBM's DRDA:
- Provides access to remote DRDA-compliant databases via standard SQL.
- No user application is required on the AS (application server) to receive and process the TPF data.
- Provides for single line and block queries, as well as transaction loggging and bulk data transfer.
- TPF data can be redirected to other DRDA-compliant databases with little or no impact to the TPF application.
- Allows decision support marketing, and other business critical data to be easily transferred to a relational database with better analysis tools.
- Inactive TPF data can be archived on higher density, less expensive storage media such as optical disk.
- Less online TPF data reduces recoup and capture times.
- Bulk data transfers can be scheduled during off peak periods.
- Large data volumes can be transferred via a CTC (channel-to-channel) connection.
System Requirements
TPFAR is compatable with any platform supporting a remote DRDA compliant database, such as but not limited to DB2 on OS/390, OS/2, AIX, or Windows NT.