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Mongo / Mongoose Aggregation - $redact and $cond issues

由 天大地大妈咪最大 提交于 2019-12-05 18:27:30

You can try $facet with $addFields for parallel aggregation in 3.4 version.

This will reduce the overall complexity and you can run groupings with its own matching input at the same time.

The below code builds the aggregation pipeline dynamically based on request object.

// Sample request
var request = {
  "name":"RINGGO",
  "year": 2017,
  "month":3,
  "week":12
};

// Build initial match document on name

var match1 = {
  name: request["name"]
};

// Build project & facet document for date based aggregation

var addFields = {};
var facet = {};

// Add year followed by year facet

if (request["year"]) {
    addFields["year"] = { "$year": "$date" },
    facet["Yearly"] = 
      [
        {
          "$match":{ "year": request["year"] }
        },
        {
          "$group": {
            "_id": {
              "name": "$name",
              "year": "$year"
            },
            "spend": { "$push":"$amount" },
            "total": { "$sum": "$amount" }
        }
      }
    ];
}

// Add month followed by month facet

if (request["month"]) {
    addFields["month"] = { "$month": "$date" };
    facet["Monthly"] = 
      [
        {
          "$match":{ "month": request["month"] }
        },
        {
          "$group": {
            "_id": {
              "name": "$name",
              "month": "$month"
            },
            "spend": { "$push":"$amount" },
            "total": { "$sum": "$amount" }
         }
      }
    ];
}

// Add week followed by week facet

if (request["week"]) {
    addFields["week"] = { "$week": "$date" };
    facet["Weekly"] = 
      [
        {
          "$match":{ "week": request["week"] }
        },
        {
          "$group": {
            "_id": {
              "name": "$name",
              "week": "$week"
            },
            "spend": { "$push":"$amount" },
            "total": { "$sum": "$amount" }
         }
      }
    ];
}

// Use aggregate builder

statements.aggregate()
        .match(match1)
        .append({"$addFields": addFields}) // No addFields stage in mongoose builder
        .facet(facet)
        .exec(function(err, data) {});

Mongo Shell Query for name/year/month/week criteria.

db.statements.aggregate({
    '$match': {
        name: 'RINGGO'
    }
}, {
    '$addFields': {
        year: {
            '$year': '$date'
        },
        month: {
            '$month': '$date'
        },
        week: {
            '$week': '$date'
        }
    }
}, {
    '$facet': {
        Yearly: [{
                '$match': {
                    year: 2017
                }
            },
            {
                '$group': {
                    _id: {
                        name: '$name',
                        year: '$year'
                    },
                    spend: {
                        '$push': '$amount'
                    },
                    total: {
                        '$sum': '$amount'
                    }
                }
            }
        ],
        Monthly: [{
                '$match': {
                    month: 3
                }
            },
            {
                '$group': {
                    _id: {
                        name: '$name',
                        month: '$month'
                    },
                    spend: {
                        '$push': '$amount'
                    },
                    total: {
                        '$sum': '$amount'
                    }
                }
            }
        ],
        Weekly: [{
                '$match': {
                    week: 12
                }
            },
            {
                '$group': {
                    _id: {
                        name: '$name',
                        week: '$week'
                    },
                    spend: {
                        '$push': '$amount'
                    },
                    total: {
                        '$sum': '$amount'
                    }
                }
            }
        ]
    }
})

Sample Response

    {
    "Yearly": [{
        "_id": {
            "name": "RINGGO",
            "year": 2017
        },
        "spend": [-3.3, -6.3, -3.3, -6.3, -3.3, -3.3],
        "total": -25.799999999999997
    }],
    "Monthly": [{
        "_id": {
            "name": "RINGGO",
            "month": 3
        },
        "spend": [-3.3, -6.3, -3.3, -6.3, -3.3, -3.3],
        "total": -25.799999999999997
    }],
    "Weekly": [{
        "_id": {
            "name": "RINGGO",
            "week": 12
        },
        "spend": [-6.3, -3.3],
        "total": -9.6
    }]
}

You can run the similar aggregation for Year/Month and Year input values.

So you can see that there is a different number of items in MonthlySpends in previous output compared to that shown in the output from the find by name. Also you can see that some of the values are being summed together in MonthlySpends when they shouldn't be.

This happens in $group 1 where $week aggregation rolls up each of two dates [15, 16] amount into week 11 and other two dates [22, 23] amount into week 12 later to show up as summed totals in MonthySpends.

标签
node.js
mongodb
mongoose
mongodb-query
aggregation-framework
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