Project specific array field in a MongoDB collection?

Let us first create a collection with documents −

> db.projectionAnElementDemo.insertOne(
...    {
...       "CustomerId":100,
...       "CustomerDetails": [
...          {
...             "CustomerName": "Chris",
...             "CustomerCountryName": "US"
...          },
...          {
...             "CustomerName": "Robert",
...             "CustomerCountryName": "UK"
...          }
...       ]
...    }
... );
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5cd31c56b64f4b851c3a13ea")
}

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

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

This will produce the following output −

{
   "_id" : ObjectId("5cd31c56b64f4b851c3a13ea"),
   "CustomerId" : 100,
   "CustomerDetails" : [
      {
         "CustomerName" : "Chris",
         "CustomerCountryName" : "US"
      },
      {
         "CustomerName" : "Robert",
         "CustomerCountryName" : "UK"
      }
   ]
}

Following is the query to project element in array field −

> db.projectionAnElementDemo.find({},{CustomerId:1, "CustomerDetails.CustomerName":1}).pretty();

This will produce the following output −

{
   "_id" : ObjectId("5cd31c56b64f4b851c3a13ea"),
   "CustomerId" : 100,
   "CustomerDetails" : [
      {
         "CustomerName" : "Chris"
      },
      {
         "CustomerName" : "Robert"
      }
   ]
}

Nishtha Thakur

Updated on 30-Jul-2019 22:30:26

• Related Questions & Answers
• How to project specific elements in an array field with MongoDB?
• Project field in MongoDB
• How to display a specific field in array using $project in MongoDB and ignore other fields?
• Return a specific field in MongoDB?
• Working with MongoDB $concatArrays in $project on existing multi-array field
• How to project specific fields from a document inside an array in Mongodb?
• Accessing array values in a MongoDB collection to fetch a specific document
• MongoDB Aggregate JSON array field for the matching field of other collection?
• Fetch specific field values in MongoDB
• Search by specific field in MongoDB
• How to check empty field in a MongoDB collection?
• Get count of array elements from a specific field in MongoDB documents?
• Add new field to every document in a MongoDB collection?
• MongoDB query to update a specific document from a collection
• How to select objects where an array contains only a specific field in MongoDB?