public Analysis analyze(Statement statement)
    {
        return analyze(statement, false);
    }
@Test
    public void testSingleGroupingSet()
    {
        // TODO: validate output
        analyze("SELECT SUM(b) FROM t1 GROUP BY ()");
        analyze("SELECT SUM(b) FROM t1 GROUP BY GROUPING SETS (())");
        analyze("SELECT a, SUM(b) FROM t1 GROUP BY GROUPING SETS (a)");
        analyze("SELECT a, SUM(b) FROM t1 GROUP BY GROUPING SETS (a)");
        analyze("SELECT a, SUM(b) FROM t1 GROUP BY GROUPING SETS ((a, b))");
    }