数组对象中的 MongoDB 查询


我们首先使用文档创建一个集合 -

> db.demo194.insertOne(
...   {
...      "_id": 101,
...      "details": {
...         "otherDetails": {
...            "List1": ["MongoDB", "MySQL"],
...            "List2": ["Java"],
...            "List3": ["MongoDB", "C"]
...         }
...      }
...   }
...);
{ "acknowledged" : true, "insertedId" : 101 }
> db.demo194.insertOne( {"_id": 102, "details": { "otherDetails": { "List1": ["Java", "C"],        "List2": ["C++"], "List3": ["Python", "Spring"] } } } );
{ "acknowledged" : true, "insertedId" : 102 }

使用 find() 方法显示集合中的所有文档 -

> db.demo194.find();

这将产生以下输出 -

{ "_id" : 101, "details" : { "otherDetails" : { "List1" : [ "MongoDB", "MySQL" ], "List2" : [ "Java" ], "List3" : [ "MongoDB", "C" ] } } }
{ "_id" : 102, "details" : { "otherDetails" : { "List1" : [ "Java", "C" ], "List2" : [ "C++" ], "List3" : [ "Python", "Spring" ] } } }

以下是查询数组对象的方法 -

> db.demo194.find({ "details.otherDetails.List1": "MongoDB" })

这将产生以下输出 -

{ "_id" : 101, "details" : { "otherDetails" : { "List1" : [ "MongoDB", "MySQL" ], "List2" : [ "Java" ], "List3" : [ "MongoDB", "C" ] } } }

更新于:2020 年 3 月 27 日

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