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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: None
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        Minor Change
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        Query 2020-01-27, Query 2020-02-10, Query 2020-02-24
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This may involve a small refactor of how $lookup and $facet introspect their respective pipelines.
- depends on
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                    SERVER-45526 Support union with sharded collections -         
- Closed
 
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- is related to
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                    SERVER-45957 Have $unionWith set a more lax HostTypeRequirement from introspecting the pipeline -         
- Backlog
 
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- related to
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                    SERVER-46277 Change nested pipeline constraint error message -         
- Backlog
 
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