Method match_updatable_columns

sql/sql_trigger.cc:1245–1277

*/

bool Trigger::match_updatable_columns(List<Item> &fields)
{
  DBUG_ASSERT(is_trg_event_on(events, TRG_EVENT_UPDATE));

  /*
    No table columns were specified in OF col1, col2 ... colN of
    the statement CREATE TRIGGER BEFORE/AFTER UPDATE. It means that this
    ON UPDATE trigger can't be fired on every UPDATE statement involving
    the target table.
  */
  if (!updatable_columns || updatable_columns->is_empty())
    return true;

  List_iterator_fast<Item> fields_it(fields);
  List_iterator_fast<LEX_CSTRING> columns_it(*updatable_columns);
  LEX_CSTRING *column_name;
  Item_field *field;

  /*
    Stop search on the first matching of a column taken from UPDATE statement
    with any column listed in trigger column list.
  */
  while ((field= (Item_field*)fields_it++))
  {
    while ((column_name= columns_it++))
    {
      if (field->field_name.streq(*column_name))
        return true;
    }
  }

  return false;
}


/**