code: static SlicePredicate slicePredicateStartCol(byte[] startColName) {
          if(startColName == null) startColName = EMPTY_BYTES;
          SliceRange sliceRange =
              new SliceRange(ByteBuffer.wrap(startColName), EMPTY_BYTE_BUFFER, false, CassandraDefs.MAX_COLS_BATCH_SIZE);
          SlicePredicate slicePred = new SlicePredicate();
          slicePred.setSlice_range(sliceRange);
          return slicePred;
      }
docs: Create a SlicePredicate that starts at the given column name, selecting up to
  {@link #MAX_COLS_BATCH_SIZE} columns.
  
  @param startColName  Starting column name as a byte[].
  @return              SlicePredicate that starts at the given column name,
  open-ended, selecting up to {@link #MAX_COLS_BATCH_SIZE}
  columns.