the process defination will change and when changed, how to deal with the old process instance this is to say , how the old process instance will carry on next ?
but when the new process and the old one has conflict , what will the engine do ?
Your example and use case is valid - I faced this problem many times. (the simplest one is - small bug in process definition (100 process instances are running according to this process definition… you have fix already but you do not have possibility to change it - this is solved by SetProcessDefinitionVersionCmd). SetProcessDefinitionVersionCmd sets only process definition version of the running process instance. It does not cope with process instance state transition to the new process definition. Process instance state transition can not be done automatically in general, but you can use activiti commands/DB to transform process instance to the new state.
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Search the forum - I like this topic very much because it is crucial for workflow platform administration.
