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Correlation sets
Correlation is used to track the multiple, long-running exchanges of messages that typically take place between a BPEL process and its partner services. Correlation sets help to route messages to the appropriate process instance based on the contents of the message body thus enabling the process instance to hold a conversation with the partner service.
A correlation set is made up of one or more properties that are defined in a WSDL file. A property alias is a rule that tells Business Process Choreographer how to map data from a message into a correlation property. You can use correlation sets in invoke, receive, pick, and reply activities to indicate which correlation sets occur in the messages that are sent and received. The values of each correlation set uniquely identify the process instance. This is true even if the process instance has already reached an end state, such as the finished state.
A correlation set is required if a process consists of more than one receive or pick activity. The receive or pick activity that initiates a new process instance does not necessarily need a correlation set. The remaining receive or pick activities, however, need a correlation set to uniquely identify the process instance to route the message to.
Related tasks:
Configure correlation sets in Integration Designer