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I tried to delete a document using db.users.remove({_id: "4f6f244f6f35438788aa138f"}) but this commmand doesn't delete anything.
> // myobject is some document that is in our db.things collection
> db.things.remove({_id: myobject._id});
I am unable to figure out ' what is myobject ?' in mongodb documentation.
> db.users.find()
{ "_id" : ObjectId("4f6cd2cb7156522f4f45b26d"), "name" : "james", "age" : 23,
"hobbies" : [ "cycling", "painting" ] }
{ "_id" : ObjectId("4f6cd3017156522f4f45b26e"), "name" : "john", "age" : 30 }
{ "_id" : ObjectId("4f6f244f6f35438788aa138f"), "name" : "john" }
{ "_id" : ObjectId("4f6f24556f35438788aa1390"), "name" : "john" }
> db.users.remove({_id: "4f6f244f6f35438788aa138f"})
666
The _id field is immutable—that is, once a document exists in your MongoDB system, it has, by definition, been assigned an _id, and you cannot change or update its primary key. That said, _id can be overridden when you insert new documents, but by default it will be populated with an ObjectID.
To delete all documents in a collection, pass an empty document ( {} ). Optional. To limit the deletion to just one document, set to true . Omit to use the default value of false and delete all documents matching the deletion criteria.
In MongoDB, each document stored in a collection requires a unique _id field that acts as a primary key. If an inserted document omits the _id field, the MongoDB driver automatically generates an ObjectId for the _id field. This also applies to documents inserted through update operations with upsert: true.
Did you try
db.things.remove({_id: ObjectId("4f6f244f6f35438788aa138f")});
You must pass an ObjectId, not a string.
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