猫鼬，按日期过滤子文档数组

Question

[{
    "_id" : ObjectId("5f3d0f13fd6fd6667f8f56d6"),
    "name" : "A",
    "prices" : [ 
        {
            "_id" : ObjectId("5f3d0f16fd6fd6667f8f57fb"),
            "d" : ISODate("2019-08-19T00:00:00.000Z"),
            "h" : 182.1,
        }, 
        {
            "_id" : ObjectId("5f3d0f16fd6fd6667f8f57fc"),
            "d" : ISODate("2019-08-20T00:00:00.000Z"),
            "h" : 182.1,
        },
        {
            "_id" : ObjectId("5f3d0f16fd6fd6667f81f57fc"),
            "d" : ISODate("2019-08-21T00:00:00.000Z"),
            "h" : 182.1,
        }
   ]
}]

输入：

from: '2019-08-20'
to: '2019-08-21'

预期输出

[{
        "_id" : ObjectId("5f3d0f13fd6fd6667f8f56d6"),
        "name" : "A",
        "prices" : [ 
            {
                "_id" : ObjectId("5f3d0f16fd6fd6667f8f57fc"),
                "d" : ISODate("2019-08-20T00:00:00.000Z"),
                "h" : 182.1,
            },
            {
                "_id" : ObjectId("5f3d0f16fd6fd6667f81f57fc"),
                "d" : ISODate("2019-08-21T00:00:00.000Z"),
                "h" : 182.1,
            }
       ]
    }]

所以我想过滤prices array，以便它仅基于变量d返回给定日期范围内的项目

是某种形式的聚合。

mongoose.model("stock").aggregate(...)

$unwind $filter，$gte，$gle的某些组合

Answer 1

您可以执行以下操作

db.collection.aggregate([
  {
    $project: {
      items: {
        $filter: {
          input: "$prices",
          as: "price",
          cond: {
            "$and": [//only date conditions
              {
                $gte: [
                  "$$price.d",
                  new Date("2019-08-20")
                ]
              },
              {
                $lte: [
                  "$$price.d",
                  new Date("2019-08-21")
                ]
              }
            ]
          }
        }
      }
    }
  }
])

play