arangosh> db._create("users", { keyOptions: { allowUserKeys: false } }); [ArangoCollection 14331, "users" (type document, status loaded)] arangosh> db.users.save({ name: "user 1" }); { "_id" : "users/14334", "_key" : "14334", "_rev" : "_U-_qW0S---" } arangosh> db.users.save({ name: "user 2", _key: "myuser" }); [ArangoError 1222: collection does not allow using user-defined keys] arangosh> db.users.save({ name: "user 3" }); { "_id" : "users/14339", "_key" : "14339", "_rev" : "_U-_qW0W---" }