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camunda / camunda-docs

Camunda 8 Documentation, including all components and features
https://docs.camunda.io/
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DMN Unique Hit Policy table has a bug #823

Open jwulf opened 2 years ago

jwulf commented 2 years ago

In the DMN Unique Hit Policy example table, "Summer" is missing and "Spring" is in twice.

Also, it is unclear in the docs what happens when more than one rule could match.

For example, if I have a discriminated union, as in the example, it is clear that at most one rule match is possible. However, what if I have something like this:

Summer and temperature > 20 Summer and temperature < 22

In this case, Summer and a temperature of 21 will match both rules. Does UNIQUE mean that it will match the first one in the table?

akeller commented 2 years ago

@saig0 can you take a look at this?

saig0 commented 2 years ago

@jwulf good point :laughing: Please note that we just copied the content from C7. It seems that you're the first one who really reads the docs :sweat_smile:

I would like to improve the DMN docs but it's a bigger effort. Currently, we don't plan to work on the docs soon. However, contributions are welcome :wink:

Regarding your question:

Does UNIQUE mean that it will match the first one in the table?

The decision table is invalid if more than one rule matches. As a result, the evaluation of the decision would fail. In the context of a process instance, it would cause an incident.