ActivitiRule allows multiple occurences of buisnesskey

[billdoor]

Hello,

long story short, i am unittesting a class and ran into unexpected behaivour, i extracted the point into a seperate test:

 @Test (expected = IllegalArgumentException.class)
    @Deployment(resources  = {"test_process.bpmn"})
    public void startProcess_duplicateBkey() {
        rule.getRuntimeService().startProcessInstanceByKey("test_process", "a1");
        rule.getRuntimeService().startProcessInstanceByKey("test_process", "a1");

         System.out.println(rule.getRuntimeService().createProcessInstanceQuery().processInstanceBusinessKey("a1", "test_process").list().size());
    }
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prints "2".

Why can i have 2 ProcessInstances of the same processdefinition with the same businesskey?

[jbarrez]

Yes, we changed that a long time ago. Many people complained about having a unique constraint on the business key, and rather it should be managed by the code calling the Activiti API. Also, the business key is often something like an id in another system, and the use case of having multiple processes for a certain object makes sense, often.

[jbarrez]

Of course, if you really need it, you can always add back the unique constraint on the database level.