code: private Mutation mutationFromTuple(Tuple t) throws IOException
      {
          Mutation mutation = new Mutation();
          if (t.get(1) == null)
          {
              if (allow_deletes)
              {
                  mutation.deletion = new Deletion();
                  mutation.deletion.predicate = new org.apache.cassandra.thrift.SlicePredicate();
                  mutation.deletion.predicate.column_names = Arrays.asList(objToBB(t.get(0)));
                  mutation.deletion.setTimestamp(FBUtilities.timestampMicros());
              }
              else
                  throw new IOException("null found but deletes are disabled, set " + PIG_ALLOW_DELETES +
                      "=true in environment or allow_deletes=true in URL to enable");
          }
          else
          {
              org.apache.cassandra.thrift.Column column = new org.apache.cassandra.thrift.Column();
              column.setName(objToBB(t.get(0)));
              column.setValue(objToBB(t.get(1)));
              column.setTimestamp(FBUtilities.timestampMicros());
              mutation.column_or_supercolumn = new ColumnOrSuperColumn();
              mutation.column_or_supercolumn.column = column;
          }
          return mutation;
      }
docs: compose Cassandra mutation from tuple