Method delete_row

sql/sql_delete.cc:308–375

*/
template <bool replace>
int TABLE::delete_row(bool treat_versioned)
{
  int err= 0;
  bool remembered_pos= false;
  uchar *del_buf= record[replace ? 1 : 0];
  bool delete_row= !treat_versioned
                   || in_use->lex->vers_conditions.delete_history
                   || versioned(VERS_TRX_ID)
                   || !vers_end_field()->is_max(
                           vers_end_field()->ptr_in_record(del_buf));

  if (!delete_row)
  {
    if ((err= file->extra(HA_EXTRA_REMEMBER_POS)))
      return err;
    remembered_pos= true;

    if (replace)
    {
      store_record(this, record[2]);
      restore_record(this, record[1]);
    }
    else
    {
      store_record(this, record[1]);
    }
    vers_update_end();

    Field *row_start= vers_start_field();
    Field *row_end= vers_end_field();
    // Don't make history row with negative lifetime
    delete_row= row_start->cmp(row_start->ptr, row_end->ptr) > 0;

    if (likely(!delete_row))
      err= file->ha_update_row(record[1], record[0]);
    if (unlikely(err))
    {
      /*
        MDEV-23644: we get HA_ERR_FOREIGN_DUPLICATE_KEY iff we already got
        history row with same trx_id which is the result of foreign key
        action, so we don't need one more history row.

        Additionally, delete the row if versioned record already exists.
        This happens on replace, a very fast sequence of inserts and deletes,
        or if timestamp is frozen.
      */
      delete_row= err == HA_ERR_FOUND_DUPP_KEY
                  || err == HA_ERR_FOUND_DUPP_UNIQUE
                  || err == HA_ERR_FOREIGN_DUPLICATE_KEY;
      if (!delete_row)
        return err;
    }

    if (delete_row)
      del_buf= record[1];

    if (replace)
      restore_record(this, record[2]);