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    Type:Task 
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    Resolution: Fixed
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    Priority:Major - P3 
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    Affects Version/s: None
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    Component/s: Aggregation Framework
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    None
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        Fully Compatible
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        Query 2018-07-16, Query 2018-07-30
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Add the ability for $out to write to an existing collection, rather than writing to a temporary collection and renaming to replace the target.
- depends on
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                    SERVER-35893 Update $out to accept new syntax -         
- Closed
 
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- is depended on by
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                    SERVER-36259 Allow aggregations with $out to be run in a transaction when the "mode" does not perform DDL operations -         
- Backlog
 
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                    SERVER-12280 allow $out to append to/merge with existing collection instead of replacing it -         
- Closed
 
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- is related to
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                    SERVER-18027 Support aggregation $out to sharded collection -         
- Closed
 
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