public List<ColumnMetadata> getColumnsMetadata()
    {
        return columnsMetadata;
    }
@Test
    public void testColumnMetadata()
    {
        assertEquals(prometheusTable.getColumnsMetadata(), ImmutableList.of(
                new ColumnMetadata("labels", varcharMapType),
                new ColumnMetadata("timestamp", TIMESTAMP_WITH_TIME_ZONE),
                new ColumnMetadata("value", DoubleType.DOUBLE)));
    }