Restrictions

There are restrictions to the database coordination support.

The following restrictions apply:

• The ability to coordinate database updates within IBM MQ units of work is not supported in an MQI client application. The use of MQBEGIN in a client application fails. A program that calls MQBEGIN must run as a server application on the same machine as the queue manager. Note: A server application is a program that has been linked with the necessary IBM MQ server libraries; a client application is a program that has been linked with the necessary IBM MQ client libraries. See Building applications for IBM MQ MQI clients and Building a procedural application for details on compiling and linking programs that you write in a procedural language.
• The database server can reside on a different machine from the queue manager server, as long as the database client is installed on the same machine as the queue manager, and it supports this function. Consult the database product's documentation to determine whether their client software can be used for two-phase commit systems.
• Although the queue manager behaves as a resource manager (for the purposes of being involved in Scenario 2 global units of work), it is not possible to make one queue manager coordinate another queue manager within its Scenario 1 global units of work.