private Transaction.Operation createOrSet(Path path, byte[] data) {
        return db.exists(path) ? CuratorOperations.setData(path.getAbsolute(), data)
                                            : CuratorOperations.create(path.getAbsolute(), data);
    }
Returns a given number of unique provision indices
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/CuratorDb.java