code: public final void clearRowData() {
          assert(verifyTableInvariants());
          m_buffer.position(m_rowStart);
          m_buffer.putInt(0);
          m_rowCount = 0;
          m_activeRowIndex = INVALID_ROW_INDEX;
          assert(verifyTableInvariants());
      }
docs: Delete all row data. Column data is preserved.
  Useful for reusing an <tt>VoltTable</tt>.