code: private void commitDeletes(DBTransaction dbTran, long timestamp) {
          Map<String, Set<ByteBuffer>> rowDeleteMap = CassandraTransaction.getRowDeletionMap(dbTran);
          if (rowDeleteMap.size() == 0) {
              return;
          }
          
          // Iterate through all ColumnFamilies
          for (String colFamName : rowDeleteMap.keySet()) {
              // Delete each row in this key set.
              Set<ByteBuffer> rowKeySet = rowDeleteMap.get(colFamName);
              for (ByteBuffer rowKey : rowKeySet) {
                  removeRow(timestamp, rowKey, new ColumnPath(colFamName));
              }
          }
      }
docs: Commit all row-deletions in the given MutationMap, if any, using the given timestamp.