I am using these components:
celery 5.4.0django-celery-beat 2.8.1django-celery-results 2.6.0django 5.2- MySQL 5.7.44
- Python 3.12.8
and can observe errors when starting up Celery Beat and having at least one periodic task active. This error did not get raised in 2.8.0.
Steps to reproduce:
- Have a basic Django setup
- Start MySQL
- Run Django migrations:
./manage.py migrate
- Start Beat:
celery -A myapp beat --scheduler django_celery_beat.schedulers:DatabaseScheduler to create the celery.backend_cleanup task
- Stop and restart Beat
- Observe this error:
...
[2025-07-28 15:11:14,380: WARNING/MainProcess] raise get_mysql_exception(
[2025-07-28 15:11:14,380: WARNING/MainProcess] django.db.utils
[2025-07-28 15:11:14,380: WARNING/MainProcess] .
[2025-07-28 15:11:14,380: WARNING/MainProcess] ProgrammingError
[2025-07-28 15:11:14,380: WARNING/MainProcess] :
[2025-07-28 15:11:14,380: WARNING/MainProcess] (1064, "1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '% 24) ELSE CAST(U0.`hour` AS signed integer) END IN (13, 14, 15, 16, 17, 4)))) A' at line 1", '42000')
Using the general query log and --log-raw option of MySQL I identified the issue in this SQL query:
SELECT
`django_celery_beat_periodictask`.`id`,
`django_celery_beat_periodictask`.`name`,
`django_celery_beat_periodictask`.`task`,
`django_celery_beat_periodictask`.`interval_id`,
`django_celery_beat_periodictask`.`crontab_id`,
`django_celery_beat_periodictask`.`solar_id`,
`django_celery_beat_periodictask`.`clocked_id`,
`django_celery_beat_periodictask`.`args`,
`django_celery_beat_periodictask`.`kwargs`,
`django_celery_beat_periodictask`.`queue`,
`django_celery_beat_periodictask`.`exchange`,
`django_celery_beat_periodictask`.`routing_key`,
`django_celery_beat_periodictask`.`headers`,
`django_celery_beat_periodictask`.`priority`,
`django_celery_beat_periodictask`.`expires`,
`django_celery_beat_periodictask`.`expire_seconds`,
`django_celery_beat_periodictask`.`one_off`,
`django_celery_beat_periodictask`.`start_time`,
`django_celery_beat_periodictask`.`enabled`,
`django_celery_beat_periodictask`.`last_run_at`,
`django_celery_beat_periodictask`.`total_run_count`,
`django_celery_beat_periodictask`.`date_changed`,
`django_celery_beat_periodictask`.`description`
FROM
`django_celery_beat_periodictask`
LEFT OUTER JOIN `django_celery_beat_clockedschedule` ON
(`django_celery_beat_periodictask`.`clocked_id` = `django_celery_beat_clockedschedule`.`id`)
WHERE
(`django_celery_beat_periodictask`.`enabled` = 1
AND NOT (((`django_celery_beat_clockedschedule`.`clocked_time` > '2025-07-29 14:05:32.092804'
AND `django_celery_beat_clockedschedule`.`clocked_time` IS NOT NULL
AND `django_celery_beat_periodictask`.`clocked_id` IS NOT NULL)
OR (`django_celery_beat_periodictask`.`crontab_id` IS NOT NULL
AND `django_celery_beat_periodictask`.`crontab_id` IN (
SELECT
U0.`id` AS `id`
FROM
`django_celery_beat_crontabschedule` U0
WHERE
(U0.`hour` REGEXP BINARY '^\\d+$'
AND NOT (CASE
WHEN (U0.`timezone` = 'UTC') THEN (((CAST(U0.`hour` AS signed integer) + 0) + 24) %% 24)
ELSE CAST(U0.`hour` AS signed integer)
END IN (12, 13, 14, 15, 16, 4))))
AND `django_celery_beat_periodictask`.`crontab_id` IS NOT NULL))))
Notice the double %% being semantically incorrect, its meant to be a single %. This seems to stem from
but I am unsure where the conversion from
% to
%% is happening.
I am using these components:
celery5.4.0django-celery-beat2.8.1django-celery-results2.6.0django5.2and can observe errors when starting up Celery Beat and having at least one periodic task active. This error did not get raised in 2.8.0.
Steps to reproduce:
./manage.py migratecelery -A myapp beat --scheduler django_celery_beat.schedulers:DatabaseSchedulerto create thecelery.backend_cleanuptaskUsing the general query log and
--log-rawoption of MySQL I identified the issue in this SQL query:Notice the double
%%being semantically incorrect, its meant to be a single%. This seems to stem fromdjango-celery-beat/django_celery_beat/schedulers.py
Line 338 in f1f239c
%to%%is happening.