for (IColumn c : row.cf)
{
if (c.isMarkedForDelete())
continue;
ByteBuffer[] current = composite.split(c.name());
// If current differs from previous, we've just finished a group
if (previous != null && !isSameRow(previous, current))
{
cqlRows.add(handleGroup(selection, row.key.key, previous, group, schema));
group = new HashMap<ByteBuffer, IColumn>();