Writing ODBA application programs

By using the ODBA interface, IMS DB databases can be accessed from environments that are outside the scope of control for IMS, such as Db2 for z/OS® stored procedures.

The ODBA interface is not needed within IMS-controlled regions, such as MPRs, BMPs, or IFPs, for calls to locally controlled databases.

The z/OS application programs (hereafter called the ODBA application programs) run in a separate z/OS address space that IMS regards as a separate region from the control region. The separate z/OS address space hereafter is called the z/OS application region.

The ODBA interface gains access to IMS DB through the Database Resource Adapter (DRA). The ODBA application programs (which can access any address space within the z/OS they are running in) gain access to IMS DB databases through the ODBA interface. The following figure illustrates this concept and shows the relationship between the components of this environment.

Figure 1. z/OS application region's connection to IMS DB
Begin figure description. ODBA beside the DRA in an z/OS application region. IMS Database Manager communicates between the z/OS application region and IMS databases. End figure description.

One z/OS application region can connect to multiple IMS DBs and multiple z/OS application regions can connect to a single IMS DB. The connection is similar to that of CICS® to DBCTL.