SERVER-45542 Support and test $unionWith aggregation stage within a transaction

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• Backlog

SERVER-45535 Support explain for $unionWith aggregation stage

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• Closed

SERVER-45537 Test currentOp for aggregation pipeline with $unionWith

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• Closed

SERVER-45538 Implement and test shard version retry logic for $unionWith sub-pipeline

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• Closed

SERVER-45540 Gate $unionWith behind FCV check and test upgrade/downgrade

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• Closed

SERVER-45541 Test killing an aggregation operation with a $unionWith stage

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• Closed

SERVER-45555 Test that the 'comment' field is propagated correctly for sharded $unionWith

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• Closed

SERVER-45562 Test that a pipeline containing a $unionWith stage uses a consistent $$NOW value

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• Closed

SERVER-45620 Have $union introspect the sub-pipeline to allow for more liberal constraints if the sub-pipeline is not constrained

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• Closed

SERVER-45675 Test that $unionWith tracks disk use appropriately

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• Closed

SERVER-45676 Test that a union sub-pipeline is allowed to contain a $search, $text, $indexStats, or $geoNear stage

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• Closed