text: drop table if exists onlineddl_test;
  create table onlineddl_test (
    id int auto_increment,
    i int not null,
    e enum('red', 'green', 'blue', 'orange', 'yellow', 'grey', 'black') not null default 'red' collate 'utf8_bin',
    primary key(id, e)
  ) auto_increment=1;
  
  insert into onlineddl_test values (null, 2, 'yellow');
  insert into onlineddl_test values (null, 3, 'grey');
  insert into onlineddl_test values (11, 5, 'yellow');
  
  drop event if exists onlineddl_test;
  delimiter ;;
  create event onlineddl_test
    on schedule every 1 second
    starts current_timestamp
    ends current_timestamp + interval 60 second
    on completion not preserve
    enable
    do
  begin
    update onlineddl_test set e='black' where e='grey';
    update onlineddl_test set e='black' where id=11;
    insert into onlineddl_test values (null, 11, 'red');
    set @last_insert_id := last_insert_id();
    insert into onlineddl_test values (@last_insert_id, 11, 'green');
    insert into onlineddl_test values (null, 13, 'green');
    insert into onlineddl_test values (null, 17, 'blue');
    set @last_insert_id := last_insert_id();
    update onlineddl_test set e='orange' where id = @last_insert_id;
    insert into onlineddl_test values (null, 23, null);
    set @last_insert_id := last_insert_id();
    update onlineddl_test set i=i+1, e=null where id = @last_insert_id;
  end ;;
  