arangosh> db._create("users", { keyOptions: { allowUserKeys: false } });
[ArangoCollection 15167, "users" (type document, status loaded)]
arangosh> db.users.save({ name: "user 1" });
{
"_id" : "users/15170",
"_key" : "15170",
"_rev" : "15170"
}
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/15175",
"_key" : "15175",
"_rev" : "15175"
}