After that enchantment, each worker could request multiple assignment-batches, before its previous batches were processed by the Controller. This means that for each batch that was processed, the Controller was deleting from the "assignment" table, all the assignments (-batches) delivered to the Worker that brought that batch, even though the "attempt" and "payload" records for the rest of the batches were not inserted in the DB yet. So in a new assignments-batch request, the same publications that were already under processing, were delivered to the same or other Workers.
Now, for each finished batch, only the assignments of that batch are deleted from the "assignment" table.
Lampros Smyrnaios
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