class DbSetId {

    @NonNull
    public static DbSetId root(@NonNull String... dimColumns) throws IllegalArgumentException {
        for (String o : dimColumns) {
            if (o == null) {
                throw new IllegalArgumentException("Columns cannot be null");
            }
        }
        return new DbSetId(Arrays2.EMPTY_STRING_ARRAY, dimColumns.clone());
    }

    private  DbSetId(@NonNull String[] dimValues, @NonNull String[] dimColumns);

}