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  1. Documentation
  2. DOCS-12588

Document implication of sharded txn on clusterTime in change stream event

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      Currently the documentation for clusterTime in a change stream event says:

      For events that happened as part of a multi-document transaction, the associated change stream notifications will have the same clusterTime value, namely the time when the transaction was committed

      While this is still factually correct in MongoDB 4.2, it implies something that may not be true: that two events with the same clusterTime ALWAYS are part of the same transaction. As schwerin pointed out to me, two transactions that are not causally consistent with each other, and that execute on two different shards, could end up with the same clusterTime for their associated change stream events.

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            kay.kim@mongodb.com Kay Kim (Inactive)
            jeff.yemin@mongodb.com Jeffrey Yemin
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              Created:
              Updated:
              Resolved:
              4 years, 37 weeks, 1 day ago