Method rowid_table_deletes

sql/sql_delete.cc:1627–1733

Implements the inner loop of nested-loops join within multi-DELETE execution. @param table The table from which to delete. @param ignore If used, all non fatal errors will be translated to warnings and we should not break the row-by-row iteration. @return Status code @retval 0 All ok. @retval 1 Triggers or handler reported error. @retval -1 End of file from handler. *

   @retval -1 End of file from handler.
*/
int multi_delete::rowid_table_deletes(TABLE *table, bool ignore)
{
  int local_error= 0;
  ha_rows last_deleted= deleted;
  DBUG_ENTER("rowid_table_deletes");
  TABLE *err_table= nullptr;

  bool will_batch= !table->file->start_bulk_delete();
  TABLE *tmp_table= tmp_tables[table_being_deleted->shared];
  tmp_table->file->extra(HA_EXTRA_CACHE);  // Change to read cache
  if (unlikely((local_error= table->file->ha_rnd_init(0))))
  {
    err_table= table;
    goto err;
  }
  table->file->extra(HA_EXTRA_NO_CACHE);
  if (unlikely((local_error= tmp_table->file->ha_rnd_init(1))))
  {
    err_table= tmp_table;
    goto err;
  }

  while (!thd->killed)
  {
    if (unlikely((local_error=
                  tmp_table->file->ha_rnd_next(tmp_table->record[0]))))
    {
      if (local_error == HA_ERR_END_OF_FILE)
      {
        local_error= 0;
        break;
      }
      err_table= tmp_table;
      goto err;
    }

    DBUG_ASSERT(!tmp_table->field[0]->is_null());
    String rowid;
    tmp_table->field[0]->val_str(&rowid);
    if (unlikely((local_error= table->file->ha_rnd_pos(table->record[0],
                                                       (uchar*)rowid.ptr()))))
    {
      // Table aliased to itself had key deleted already
      continue;
    }

    bool trg_skip_row= false;

    if (table->triggers &&
        unlikely(table->triggers->process_triggers(thd, TRG_EVENT_DELETE,
                                                   TRG_ACTION_BEFORE, FALSE,
                                                   &trg_skip_row)))
    {
      err_table= table;
      local_error= 1;
      break;
    }