DB2 Support for the DRDA Levels

DB2 provides support for distributed requests using three of the DRDA levels: remote request, remote unit of work, and distributed unit of work.

Remote Request

Applications can implement remote request capability by issuing a single request to a single location within a single unit of work. This approach is the easiest but least flexible method of coding distributed DB2 access.

Remote Unit of Work

To utilize RUW within an application program, these rules must be followed:

• Each request must be for a single location.

• Each unit of work can contain multiple requests.

• Each unit of work must access data from a single location only.

A single application program can access data from multiple locations using RUW but not within the same unit of work. The programmer must be cognizant of this fact and therefore code the program appropriately.

Distributed Unit of Work

An application utilizes DUW if these rules are followed:

• Each request must be for a single location.

• Each unit of work can contain multiple requests.

• Each unit of work can access data at multiple locations.

DB2 supports both private protocol DUW and full DRDA DUW.