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  1. Documentation
  2. DOCS-12513

Docs for SERVER-39418: Ban atClusterTime with enableMajorityReadConcern:false

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    Description

      Description

      Description:

      We will no longer support 'atClusterTime' with enableMajorityReadConcern:false. The external-facing implication of this is that:

      • in 4.2 with enableMajorityReadConcern:false, we will not support transactions in sharded clusters with readConcern level 'snapshot'. Done as part of earlier ticket. but need to update error message
      • (Note that 4.0 does not support transactions in sharded clusters at all, and 4.2 with enableMajorityReadConcern:false only supports single-shard transactions.) Done as part of earlier ticket.
      • 4.0 users should be cautioned that if they are using enableMajorityReadConcern:false and single replica set transactions, then they may wish to avoid readConcern level 'snapshot' if they may transition to using a sharded cluster in 4.2, since this will break their application.
      • In 4.2 with enableMajorityReadConcern:false, single-shard transactions will support readConcern levels 'local' and 'majority'.

      Engineering Ticket Description:

      This means that single-shard transactions on enableMajorityReadConcern:false shards cannot be run with readConcern level snapshot.

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            kay.kim@mongodb.com Kay Kim (Inactive)
            kay.kim@mongodb.com Kay Kim (Inactive)
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            Dates

              Created:
              Updated:
              Resolved:
              4 years, 38 weeks ago