To get the opposite of $addToSet to '$removeFromSet', use the $pull operator.
Let us create a collection with a document. The query to create a collection with a document is as follows −
> db.oppositeAddToSetDemo.insertOne({"StudentName":"John","StudentHobby":["Cricket","Cooking","Drawing"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c8eddcc2f684a30fbdfd588") } > db.oppositeAddToSetDemo.insertOne({"StudentName":"Carol","StudentHobby":["Cricket","Dance","Hiking"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c8eddfd2f684a30fbdfd589") } > db.oppositeAddToSetDemo.insertOne({"StudentName":"David","StudentHobby":["Learning","Photography"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ede272f684a30fbdfd58a") }
Display all documents from a collection with the help of find() method. The query is as follows −
> db.oppositeAddToSetDemo.find().pretty();
The following is the output −
{ "_id" : ObjectId("5c8eddcc2f684a30fbdfd588"), "StudentName" : "John", "StudentHobby" : [ "Cricket", "Cooking", "Drawing" ] } { "_id" : ObjectId("5c8eddfd2f684a30fbdfd589"), "StudentName" : "Carol", "StudentHobby" : [ "Cricket", "Dance", "Hiking" ] } { "_id" : ObjectId("5c8ede272f684a30fbdfd58a"), "StudentName" : "David", "StudentHobby" : [ "Learning", "Photography" ] }
Here is the query for opposite of $addToSet to '$removeFromSet' using $pull operator −
> db.oppositeAddToSetDemo.update( ... {"StudentName": "John"}, ... {$pull: { "StudentHobby": "Cooking"}}); WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
Let us check the documents from the collection using find(). The query is as follows:
> db.oppositeAddToSetDemo.find().pretty();
The following is the output −
{ "_id" : ObjectId("5c8eddcc2f684a30fbdfd588"), "StudentName" : "John", "StudentHobby" : [ "Cricket", "Drawing" ] } { "_id" : ObjectId("5c8eddfd2f684a30fbdfd589"), "StudentName" : "Carol", "StudentHobby" : [ "Cricket", "Dance", "Hiking" ] } { "_id" : ObjectId("5c8ede272f684a30fbdfd58a"), "StudentName" : "David", "StudentHobby" : [ "Learning", "Photography" ] }