Method create_trigger

sql/sql_trigger.cc:930–1174

*/

bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables,
                                         String *stmt_query,
                                         DDL_LOG_STATE *ddl_log_state,
                                         DDL_LOG_STATE *ddl_log_state_tmp_file)
{
  LEX *lex= thd->lex;
  TABLE *table= tables->table;
  char file_buff[FN_REFLEN], trigname_buff[FN_REFLEN];
  char backup_file_buff[FN_REFLEN];
  char trg_definer_holder[USER_HOST_BUFF_SIZE];
  LEX_CSTRING backup_name= { backup_file_buff, 0 };
  LEX_CSTRING file, trigname_file;
  struct st_trigname trigname;
  String trigger_definition;
  Trigger *trigger= 0;
  int error;
  bool trigger_exists;
  DBUG_ENTER("create_trigger");

  if (check_for_broken_triggers())
    DBUG_RETURN(true);

  /* Trigger must be in the same schema as target table. */
  if (!table->s->db.streq(lex->spname->m_db))
  {
    my_error(ER_TRG_IN_WRONG_SCHEMA, MYF(0));
    DBUG_RETURN(true);
  }

  if (sp_process_definer(thd))
    DBUG_RETURN(true);

  /*
    Let us check if all references to fields in old/new versions of row in
    this trigger are ok.

    NOTE: We do it here more from ease of use standpoint. We still have to
    do some checks on each execution. E.g. we can catch privilege changes
    only during execution. Also in near future, when we will allow access
    to other tables from trigger we won't be able to catch changes in other
    tables...

    Since we don't plan to access to contents of the fields it does not
    matter that we choose for both OLD and NEW values the same versions
    of Field objects here.
  */
  old_field= new_field= table->field;

  if (iterate_trigger_fields_and_run_func(
        lex->sphead->m_trg_table_fields,
        [thd, table] (Item_trigger_field* trg_field)
        {
          /*
            NOTE: now we do not check privileges at CREATE TRIGGER time.
            This will be changed in the future.
          */
          trg_field->setup_field(thd, table, nullptr);