Remote unit of work (RUW) is a form of distributed relational database processing in which an application program can access data on a remote database within a unit of work. A remote unit of work can include more than one relational database request, but all requests must be made to the same remote database. All requests to a relational database must be completed (either committed or rolled back) before requests can be sent to another relational database.
This is shown in the following figure.
Remote unit of work is application-directed distribution because the application program must connect to the correct relational database system before issuing the requests. However, the application program only needs to know the name of the remote database to make the correct connection.
Remote unit of work support enables an application program to read or update data at more than one location. However, all the data that the program accesses within a unit of work must be managed by the same relational database management system. For example, the shop inventory application program must commit its inventory and accounts receivable unit of work before it can read or update tables that are in another location.
In remote unit of work processing, each computer has an associated relational database management system and an associated application requester program that help process distributed relational data requests. This allows you or your application program to request remote relational data in much the same way as you request local relational data.