Remove array elements from MongoDB collection using update() and $pull

Let us first create a collection containing documents -

> db.removingAnArrayElementDemo.insertOne({"UserMessage":["Hi","Hello","Bye"]}); { "acknowledged" : true, "insertedId" : ObjectId("5cef97bdef71edecf6a1f6a4") }

Display all the documents in the collection with the help of find() method -

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

Output

{ "_id" : ObjectId("5cef97bdef71edecf6a1f6a4"), "UserMessage" : [ "Hi", "Hello", "Bye" ] }

The following is the query to delete array elements from MongoDB -

> db.removingAnArrayElementDemo.update( {_id:ObjectId("5cef97bdef71edecf6a1f6a4")}, { "$pull": { "UserMessage": "Hello" } } ); WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })

Let’s check the document again:

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

Output

{ . "_id" : ObjectId("5cef97bdef71edecf6a1f6a4"), "UserMessage" : [ "Hi", "Bye" ] }

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