文檔中查找子元素MongoDB中

Question

我正在下面的文件

{ 
"_id" : 123344223, 
"firstName" : "gopal", 
"gopal" : [ 
    { 
     "uuid" : "123", 
     "name" : "sugun", 
     "sudeep" : [ 
      { 
       "uuid" : "add32", 
       "name" : "ssss" 
      }, 
      { 
       "uuid" : "fdg456", 
       "name" : "gfg" 
      } 
     ] 
    }, 
    { 
     "uuid" : "222", 
     "name" : "kiran" 
    } 
] 
} 

我想我的輸出如下

{ 
"_id" : 456, 
"gopal" : [ 
    { 
     "uuid" : "123", 
     "name" : "sugun", 
     "sudeep" : [ 
      { 
       "uuid" : "add32", 
       "name" : "ssss" 
      } 
     ] 
    } 
] 
} 

，我試圖像

db.People.findOne({_id:123},{gopal:{$elemMatch:{uuid:"123",sudeep:{$elemMatch:{uuid:"add32"}}}}}); 

很多東西

但無論我嘗試它返回這樣的文件

{ 
"_id" : 123, 
"gopal" : [ 
    { 
     "uuid" : "123", 
     "name" : "sugun", 
     "sudeep" : [ 
      { 
       "uuid" : "add32", 
       "name" : "ssss" 
      }, 
      { 
       "uuid" : "fdg456", 
       "name" : "gfg" 
      } 
     ] 
    } 
] 
} 

你能幫忙嗎？

Answer 1

您是否知道MongoDB aggregation pipeline？在聚合管道

> db.people.aggregate([ 
    {$match: {_id: 123}}, 
    {$unwind: "$gopal"}, 
    {$unwind: "$gopal.sudeep"}, 
    {$match: {"gopal.uuid": "123", "gopal.sudeep.uuid" : "add32"}} 
]) 

輸出

{ 
     "_id" : 123, 
     "firstName" : "gopal", 
     "gopal" : { 
       "uuid" : "123", 
       "name" : "sugun", 
       "sudeep" : { 
         "uuid" : "add32", 
         "name" : "ssss" 
       } 
     } 
} 

Answer 2

使用$開卷

db.People.aggregate（[{$比賽：{_ ID： '123'}}，{$匹配：{ gopal.uuid：'123'}}，{$ unwind：'$ sudeep'}，{$ match：{uuid：'add32'}}]）