Details
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Improvement
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Resolution: Fixed
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Major - P3
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None
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None
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None
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Fully Compatible
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Query Optimization 2021-04-05, Query Optimization 2021-04-19, Query Optimization 2021-05-03, Query Optimization 2021-05-17
Description
Semantically, the $setWindowFields stage does not guarantee an output order so users may add a $sort stage to get the order they want. Since the physical implementation for $setWindowFields happens to have a guaranteed order, we should drop (or coalesce or swap) the user $sort if its not necessary.