Service Gateway for DB2 is a server interface to DB2 data that you use for concurrent real-time access to DB2 data from TIBCO Object Service Broker. It can execute only in a z/OS environment and connect to z/OS DB2.
Initially, the Gateway generates dynamic Structured Query Language (SQL) to access DB2 data. When your TIBCO Object Service Broker application is complete, you can collect TIBCO Object Service Broker DB2 access statements and use them to generate static SQL, as described in
Collecting TIBCO Object Service Broker DB2 Access Statements. Generating static SQL is described in
Chapter 3, Using Static SQL.
The Gateway ensures that data is presented to TIBCO Object Service Broker rules in a manner consistent with TIBCO Object Service Broker behavior. You can access DB2 data by doing the following:
The initializer program (S6BDB2M) is passed a number of parameters, including one that instructs it to attach a specified number of Gateway tasks, allowing multiple Gateways in a single Gateway address space. The initializer program is used only to start up a Gateway and maintain the Gateway subtasks. It establishes communication to the Data Object Broker using the TIBCO Object Service Broker Communication Subsystem and to the DB2 subsystem using the Call Attach Facility (CAF) CONNECT.
Each Gateway task establishes a task-level connection to TIBCO Object Service Broker. When the Execution Environment requests access to DB2 data, a CAF OPEN PLAN is issued. Gateway parameters are used to determine the length of time that the connection to the DB2 subsystem is active (PLAN stays open). The Gateway supports read/write access to DB2 data.
The following illustration shows how data is sent to the Data Object Broker in variable length buffers up to a maximum of 31 KB. If a single request requires more than 31 KB of data, multiple 31 KB buffers are sent until the request is complete.
You can configure the Data Object Broker and the Service Gateway for DB2 to reside on different hosts and/or operating systems (z/OS, Windows, or Solaris). Service Gateway for DB2 must be in the same logical partition as the DB2 database system. Refer to
Connecting the Gateway to a Windows, or Solaris Data Object Broker for additional information.
TIBCO Object Service Broker for z/OS Installing and Operating or
TIBCO Object Service Broker for Open Systems Installing and Operating for more information on communications requirements.