We recently discovered that messages being sent to Microsoft Azure Event Hub targets are not maintaining transactional integrity. We opened a case with Qlik support and they confirmed this is the case and the documentation is incorrect.
The internal support team gave us this option: "As discussed, your options are either to use 'cdcOnAirBatchesPerClient' & 'cdcMaxClientsPerHub' internal parameters(with value=1) in order to keep only 1 batch on air during CDC, that way it should ensure that the order will be kept, however, it is a tradeoff with bad performance." We tested those 2 internal parameters and they did address the transactional integrity issue but performance was terrible as we saw latency steadily grow and were soon hours behind.
We would like Qlik to fix the Event Hub client so that transactional integrity is maintained.
Microsoft suggested using the Kafka client as a work-around and we are currently using that method. Here is URL to the documentation.