arangosh> db._create("users", { keyOptions: { allowUserKeys: false } }); [ArangoCollection 15058, "users" (type document, status loaded)] arangosh> db.users.save({ name: "user 1" }); { "_id" : "users/15061", "_key" : "15061", "_rev" : "15061" } 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/15066", "_key" : "15066", "_rev" : "15066" }