Filter by several array elements in MongoDB?

For this, you can use $elemMatch operator. The $elemMatch operator matches documents that contain an array field with at least one element that matches all the specified query criteria. Let us first create a collection with documents −

> db.filterBySeveralElementsDemo.insertOne(    "_id":100,    "StudentDetails": [       {          "StudentName": "John",          "StudentCountryName": "US",       },       {          "StudentName": "Carol",          "StudentCountryName": "UK"       }    ] } ); { "acknowledged" : true, "insertedId" : 100 } > db.filterBySeveralElementsDemo.insertOne(    {       "_id":101,       "StudentDetails": [          {             "StudentName": "Sam",             "StudentCountryName": "AUS",          },          {             "StudentName": "Chris",             "StudentCountryName": "US"          }       ]    } ); { "acknowledged" : true, "insertedId" : 101 }

Following is the query to display all documents from a collection with the help of find() method −

> db.filterBySeveralElementsDemo.find().pretty();

This will produce the following output −

{    "_id" : 100,    "StudentDetails" : [       {          "StudentName" : "John",          "StudentCountryName" : "US"       },       {          "StudentName" : "Carol",          "StudentCountryName" : "UK"       }    ] } {    "_id" : 101,    "StudentDetails" : [       {          "StudentName" : "Sam",          "StudentCountryName" : "AUS"       },       {          "StudentName" : "Chris",          "StudentCountryName" : "US"       }    ] }

Following is the query to filter by several array elements −

> db.filterBySeveralElementsDemo.find({ StudentDetails: { $elemMatch: { StudentName: 'Sam', StudentCountryName: 'AUS' }}}).pretty();

This will produce the following output −

{    "_id" : 101,    "StudentDetails" : [       {          "StudentName" : "Sam",          "StudentCountryName" : "AUS"       },       {          "StudentName" : "Chris",          "StudentCountryName" : "US"       }    ] }