@Test
public void testMultipleColumns() {

    DataSetLookup lookup = MULTIPLE_COLUMNS.newDataSetLookup(METADATA);
    assertEquals(lookup.getDataSetUUID(), "test");
    List<DataSetOp> opList = lookup.getOperationList();
    assertEquals(opList.size(), 1);
    List<DataSetGroup> groupList = lookup.getOperationList(DataSetGroup.class);
    assertEquals(groupList.size(), 1);
    DataSetGroup groupOp = groupList.get(0);
    assertNotNull(groupOp);
    ColumnGroup cg = groupOp.getColumnGroup();
    assertNull(cg);
    assertEquals(groupOp.getGroupFunctions().size(), MULTIPLE_COLUMNS.getMinColumns());
    for (int i = 0; i < MULTIPLE_COLUMNS.getMinColumns(); i++) {
        GroupFunction gf = groupOp.getGroupFunction(METADATA.getColumnId(i));
        assertNotNull(gf);
        assertEquals(gf.getSourceId(), METADATA.getColumnId(i));
        assertEquals(gf.getColumnId(), METADATA.getColumnId(i));
        assertNull(gf.getFunction());
    }
}