Checklist: Making Correct Use of Correlations 

Check your correlations for the following:

·        Correlations Using Payload Fields: Check that all fields that you used to define a correlation are available in the payload of the messages involved.

·        Uniqueness: Check that you have defined all correlations uniquely.

If, for example, multiple factories use the same material number, a correlation that uses the material number alone is not sufficient to uniquely determine all the messages that belong together. In this case you need to define the correlation by using the material number and the factory.

·        Validity: Check that you have defined the validity of correlations correctly. For each correlation, check whether it can be defined as a local correlation.

A local correlation is only valid for the block for which it is defined. Once the block has been processed, the correlation is no longer active.

If the validity of a correlation is not restricted correctly, the following problems can occur:

¡        Messages that satisfy an active correlation are continued to be assigned to a running integration process. The integration process no longer processes the messages because no processing steps are waiting for the messages.

¡        Messages that satisfy an active correlation are continued to be assigned to a running integration process, instead of starting a new integration process.

You can avoid these problems and make it easier to follow how messages are processed by restricting correlations correctly to the required block.