Mongodb 如何在数组中获取匹配的嵌套项

如何在数组中获取匹配的嵌套项

我想返回嵌套数组中的匹配项

例如，我想筛选出在其项中包含

“A428”、“A429”

的记录

我怎么能得到它

查询 样本文件 预期结果 失败，错误为{“errmsg”：“异常：管道阶段规范对象必须仅包含一个字段。”，“代码”：16435，“确定”：0} 您应该首先

记录

，然后

匹配

元素，如下所示：

db.collection.aggregate({
    "$unwind": "$records"
}, {
    "$match": {
    "records.items": {
        "$in": ["A428 ", "A429 "]
    }
    }
}, {
    "$group": {
    "_id": "$_id",
    "records": {
        "$push": "$records"
    }
    }
}).pretty()

---

请检查以下查询：

 db.collection.aggregate([
   {"$unwind" : "$records"},
   {"$unwind" : "$records.items"},
   {"$match" : {"records.items" : {"$in" : [ "A428 ","A429 "] } } },
   {"$group" : { "_id" :  { "id" : "$_id" , "app_date" : "$records.APPL_DATE" , 
    "fun_date" : "$records.FUNC_DATE"} , 
    "records_temp" : { "APPL_DATE" : { "$first" :"$records.APPL_DATE" },
    "FUNC_DATE" : { "$first" : "$records.FUNC_DATE" } ,
    "items" : {"$push" : "$records.items"} } },
  {"$group" : { "_id" : "$_id.id", "records" : { "$push" : "$records_temp" } } }
 ]);

---

首先记录

数组，然后匹配Hi您的解决方案将失败，因为“管道阶段规范对象必须只包含一个字段”。`@newBike否，它将为您提供预期的输出。你试过了吗？仅当您尝试将任何内容推送到

\u id

之外时，才会发生此异常。

  "_id": "0007db2dac8d6482ec60c228b700c3ec",
  "records": [
    {
      "APPL_DATE": new Date("1996-03-19T08:00:00+0800"),
      "FUNC_DATE": new Date("1996-02-27T08:00:00+0800"),
      "items": [
        "A428 ",
        "     ",
        "     "
      ]
    },
    {
      "APPL_DATE": new Date("1996-03-19T08:00:00+0800"),
      "FUNC_DATE": new Date("1996-02-27T08:00:00+0800"),
      "items": [
        "A429 ",
        "     ",
        "     "
      ]
    }]

pipeline_work = [
  {
    "$unwind": "$records",
    "$match": {
      "records.items": {
        "$in": ["A428 ", "A429 "]
      }
    },
    "$group": {
      "_id": "$_id",
      "records": {
        "$push": "$records"
      }
    }
  }, {
    '$limit': 1
  }
];

db.collection.aggregate({
    "$unwind": "$records"
}, {
    "$match": {
    "records.items": {
        "$in": ["A428 ", "A429 "]
    }
    }
}, {
    "$group": {
    "_id": "$_id",
    "records": {
        "$push": "$records"
    }
    }
}).pretty()

 db.collection.aggregate([
   {"$unwind" : "$records"},
   {"$unwind" : "$records.items"},
   {"$match" : {"records.items" : {"$in" : [ "A428 ","A429 "] } } },
   {"$group" : { "_id" :  { "id" : "$_id" , "app_date" : "$records.APPL_DATE" , 
    "fun_date" : "$records.FUNC_DATE"} , 
    "records_temp" : { "APPL_DATE" : { "$first" :"$records.APPL_DATE" },
    "FUNC_DATE" : { "$first" : "$records.FUNC_DATE" } ,
    "items" : {"$push" : "$records.items"} } },
  {"$group" : { "_id" : "$_id.id", "records" : { "$push" : "$records_temp" } } }
 ]);