    @Test
    public void sort() {

        List<ETLRow> rows = new ArrayList<>();
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.DELETE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.DELETE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.DELETE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.TRUNCATE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.TRUNCATE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.UPDATE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.TRUNCATE, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));
        rows.add(new ETLRow(0, 0, "s", "t", MessageAction.INSERT, null, null, null));

        ETLBucket bucket = new ETLBucket("0", rows, null);
        new JdbcBatchLoader().sort(bucket);
        Assert.assertEquals(bucket.getParallelRows().stream().mapToLong(r -> r.size()).sum(), rows.size());
    }