: ', sort_merge_passes, '\\n',
                         'sort rows: ', sort_rows, '\\n',
                         'sort range: ', sort_range, '\\n',
                         'sort scan: ', sort_scan, '\\n',
                         'no index used: ', IF(no_index_used, 'TRUE', 'FALSE'), '\\n',
                         'no good index used: ', IF(no_good_index_used, 'TRUE', 'FALSE'), '\\n'
                         ) AS wait_info
             FROM performance_schema.events_statements_history_long WHERE thread_id = thd_id)
          UNION
          (SELECT thread_id, event_id, event_name, timer_wait, timer_start, nesting_event_id, null AS wait_info
             FROM performance_schema.events_stages_history_long WHERE thread_id = thd_id)
          UNION 
          (SELECT thread_id, event_id,
                  CONCAT(event_name ,
                         IF(event_name NOT LIKE 'wait/synch/mutex%', IFNULL(CONCAT(' - ', operation), ''), ''),
                         IF(number_of_bytes IS NOT NULL, CONCAT(' ', number_of_bytes, ' bytes'), ''),
                         IF(event_name LIKE 'wait/io/file%', '\\n', ''),
                         IF(object_schema IS NOT NULL, CONCAT('\\nObject: ', object_schema, '.'), ''),
                         IF(object_name IS NOT NULL,
                            IF (event_name LIKE 'wait/io/socket%',
                                CONCAT(IF (object_name LIKE ':0%', @@socket, object_name)),
                                object_name),
                            ''),
                          IF(index_name IS NOT NULL, CONCAT(' Index: ', index_name), ''),'\\n'
                         ) AS event_name,
                  timer_wait, timer_start, nesting_event_id, source AS wait_info
             FROM performance_schema.events_waits_history_long WHERE thread_id = thd_id)) events
    ORDER BY event_id;
    RETURN CONCAT('{',
                  CONCAT_WS(',',
                            '"rankdir": "LR"',
                            '"nodesep": "0.10"',
                            CONCAT('"stack_created": "', NOW(), '"'),
                            CONCAT('"mysql_version": "', VERSION(), '"'),
                            CONCAT('"mysql_user": "', CURRENT_USER(), '"'),
                            CONCAT('"events": [', IFNULL(json_objects,''), ']')
                           ),
                  '}');
END