DFHDBAT

DFHDBAT is the CICS Database Adapter Transformer and receives the request from DFHDLI via the Task Related User Exit (TRUE). DFHDBAT "transforms" the request into parameter lists for the next component (the Database Resource Adapter or DRA) for connection/disconnection from DBCTL and the processing of the DL/I instructions. DRA manages the connection and subsequent link between the application and DBCTL. This component manages the connections via "threads" which are actually the control block storage links used for data transfer. The DRA creates its own subtask Task Control Block (TCB) and then manages subsequent subtask TCBs for DBCTL threads as required by each application request. These threads provide the link between the two subsystems, DBCTL and CICS/ESA for each application DL/I request.

Reference Sources

"CICS/ESA and IMS/ESA With DBCTL", Phyllis Donofrio, Enterprise Systems Journal, December 1990.