switchcaseを使用してコレクション内の複数のドキュメントを更新する

$switch これはMongoDBServer3.4以降の新機能です：

MongoDB Server 3.4 ：

db.collection('shifts').aggregate([
    {
        "$match": {
            "jobId": ObjectId(job._id),
            "from": { "$gte": new Date() }
        }
    },
    {
        "$project": {
            "hourlyRate": {
                "$switch": {
                    "branches": [
                        {
                            "case": { 
                                "$not": { 
                                    "$in": [
                                        { "$dayOfWeek": "$from" }, 
                                        [1, 7] 
                                    ] 
                                } 
                            }, 
                            "then": 20 
                        },
                        { 
                            "case": { 
                                "$eq": [
                                    { "$dayOfWeek": "$from" }, 
                                    7
                                ] 
                            }, 
                            "then": 25 
                        },
                        { 
                            "case": { 
                                "$eq": [
                                    { "$dayOfWeek": "$from" }, 
                                    1 
                                ] 
                            }, 
                            "then": 30 
                        }
                    ]
                }   
            }               
        }
    }       
], function(err, docs) {
    var ops = [],
        counter = 0;

    docs.forEach(function(doc) {
        ops.push({
            "updateOne": {
                "filter": { "_id": doc._id },
                "update": { "$set": { "hourlyRate": doc.hourlyRate } }
            }
        });
        counter++;

        if (counter % 500 === 0) {
            db.collection('shifts').bulkWrite(ops, function(err, r) {
                // do something with result
            });
            ops = [];
        }
    })

    if (counter % 500 !== 0) {
        db.collection('shifts').bulkWrite(ops, function(err, r) {
            // do something with result
        }
    }       
});

MongoDB Server 3.2

 db.collection('shifts').aggregate([
    {
        "$match": {
            "jobId": ObjectId(job._id),
            "from": { "$gte": new Date() }
        }
    },
    {
        "$project": {
            "hourlyRate": {
                "$cond": [
                    {
                        "$not": { 
                            "$setIsSubset": [
                                [{ "$dayOfWeek": "$from" }], 
                                [1, 7] 
                            ] 
                        } 
                    }, 20,                                
                    { 
                        "$cond": [
                            { "$eq": [
                                { "$dayOfWeek": "$from" }, 
                                7
                            ] },
                            25,
                            { 
                                "$cond": [ 
                                    { "$eq": [
                                        { "$dayOfWeek": "$from" }, 
                                        1 
                                    ] },
                                    30,
                                    "$hourlyRate"
                                ]
                            }
                        ]
                    }                   
                ]                   
            }               
        }
    }
], function(err, docs) {
    var ops = [],
        counter = 0;

    docs.forEach(function(doc) {
        ops.push({
            "updateOne": {
                "filter": { "_id": doc._id },
                "update": { "$set": { "hourlyRate": doc.hourlyRate } }
            }
        });
        counter++;

        if (counter % 500 === 0) {
            db.collection('shifts').bulkWrite(ops, function(err, r) {
                // do something with result
            });
            ops = [];
        }
    })

    if (counter % 500 !== 0) {
        db.collection('shifts').bulkWrite(ops, function(err, r) {
            // do something with result
        }
    }       
})