Support block-based $group with $min/$max end-to-end

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    • Type: Task
    • Resolution: Fixed
    • Priority: Major - P3
    • 8.0.0-rc0
    • Affects Version/s: None
    • Component/s: None
    • None
    • Query Execution
    • Fully Compatible
    • 105
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      Given a simple timeseries collection:

      ./build/install/bin/mongod --setParameter featureFlagSbeFull=true --setParameter featureFlagTimeSeriesInSbe=true --setParameter logComponentVerbosity='{query: 5}'
> db.coll.drop()
> db.createCollection("coll", {timeseries: {timeField: "t"}})
> db.coll.insert({t: new Date(), a: 4, b: 7, c: 5})
> db.coll.insert({t: new Date(), a: 2, b: 9, c: 8})
> db.coll.insert({t: new Date(), a: 3, b: 1, c: 6})
..

      The goal of this task is to get the following queries working in block-processing mode (and to write a jstest that verifies it works). A $match is needed before the $group to force block processing, as without it the $group will use the Time Series bucket metadata to satisfy $min and $max queries without unpacking the buckets and thus without any block processing. allowDiskUse must also be set to false as block processing is only supported in this case:

      > db.coll.aggregate([{$match: {a: {$gt: 0}}}, {$group: {_id: null, x: {$min: "$a"}}}], {allowDiskUse: false})
      > db.coll.aggregate([{$match: {a: {$gt: 0}}}, {$group: {_id: null, x: {$max: "$a"}}}], {allowDiskUse: false})
      > db.coll.aggregate([{$match: {a: {$gt: 0}}}, {$group: {_id: "$c", x: {$min: "$a"}}}], {allowDiskUse: false})
      > db.coll.aggregate([{$match: {a: {$gt: 0}}}, {$group: {_id: "$c", x: {$max: "$a"}}}], {allowDiskUse: false})

            Assignee:
            Drew Paroski
            Reporter:
            Drew Paroski
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              Updated:
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