To remove object from an array in MongoDB, you can use $pull operator. The syntax is as follows:
db.yourCollectionName.update( {'_id':ObjectId("5c6ea036a0c51185aefbd14f")}, {$pull:{"yourArrayName":{"yourArrayFieldName":yourValue}}}, false,true);
To understand the above syntax, let us create a collection with document. The query to create a collection with document is as follows:
> db.removeObject.insertOne({"CustomerName":"Maxwell","CustomerAge":23, ... "CustomerDetails":[ ... { ... "CustomerId":100, ... "CustomerProduct":"Product-1" ... }, ... { ... "CustomerId":150, ... "CustomerProduct":"Product-2" ... }, ... { ... "CustomerId":200, ... "CustomerProduct":"Product-3" ... } ... ] ... }); { "acknowledged" : true, "insertedId" : ObjectId("5c6ea036a0c51185aefbd14f") }
Display all documents from a collection with the help of find() method. The query is as follows:
> db.removeObject.find().pretty();
The following is the output:
{ "_id" : ObjectId("5c6ea036a0c51185aefbd14f"), "CustomerName" : "Maxwell", "CustomerAge" : 23, "CustomerDetails" : [ { "CustomerId" : 100, "CustomerProduct" : "Product-1" }, { "CustomerId" : 150, "CustomerProduct" : "Product-2" }, { "CustomerId" : 200, "CustomerProduct" : "Product-3" } ] }
Here is the query to remove object from an array in MongoDB:
> db.removeObject.update( {'_id':ObjectId("5c6ea036a0c51185aefbd14f")}, ... {$pull:{"CustomerDetails":{"CustomerId":150}}}, ... false,true); WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
Above, we have removed object from an array. Let us display document from the collection. The query is as follows:
> db.removeObject.find().pretty();
The following is the output:
{ "_id" : ObjectId("5c6ea036a0c51185aefbd14f"), "CustomerName" : "Maxwell", "CustomerAge" : 23, "CustomerDetails" : [ { "CustomerId" : 100, "CustomerProduct" : "Product-1" }, { "CustomerId" : 200, "CustomerProduct" : "Product-3" } ] }