<t>Correct!!<br/>
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The fundamental difference between EventHubs and Topics is - TOPICS offer per-message semantics - whereas, EventHubs - offer Stream Semantics - implies, one should not expect any per-message feature/semantics with EventHubs.<br/>
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Any middle-tier providing per-message features comes with the processing overhead (the tax)!!<br/>
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For Ex: Per message Duplicate detection, Receive confirmation per message (topics have a Message.Complete to ack Msg received) - are all Topic features. EventHubs narrows-down the feature set to provide a better low-latency/high-throughput solution. <br/>
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To visualize features like at-least-once delivery (of per msg is not available in EventHubs) is to translate it to stream semantics - Read until a point in a Given eventHub partition and checkpoint and let your application which is consuming those events handle the at-least-once delivery.<br/>
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more on Event Hubs...</t>
