When connecting in a distributed unit of work application, there
are many considerations.
- If the unit of work will perform updates at more than one application
server and commitment control will be used, all connections over which updates
will be done should be made using commitment control. If the connections are
done not using commitment control and later committable updates are performed,
read-only connections for the unit of work are likely to result.
- Other non-SQL commit resources, such as local files, DDM files, and commitment
control API resources, will affect the updatable and read-only status of a
connection.
- If connecting using commitment control to an application server that does
not support distributed unit of work (for example, a V4R5 iSeries™ using
TCP/IP), that connection will be either updatable or read-only. If the connection
is updatable it is the only updatable connection. As of V5R3, updates done
as a result of triggers or user defined functions activated during a database
query will be taken into consideration during DRDA® two-phase-commit operations.