Clean Up Scheduled Triggers Data

Introduction

Hasura stores event data associated with Scheduled Triggers in the "hdb_catalog" schema of the Hasura Metadata database.

If there are lots of events, the events tables can get huge and you may want to prune them. You can use any of the following options to prune your event data depending on your need.

Note

For each project in Hasura Cloud the retention period for cron events and invocation logs for cron triggers is 1 month.

Tables involved

Cron triggers have two tables managed by Hasura:

1. hdb_catalog.hdb_cron_events: Table that stores all the cron events.
2. hdb_catalog.hdb_cron_event_invocation_logs: Table that stores all the HTTP requests and their responses of the cron events invocations.

Similarly, scheduled events also have two tables managed by Hasura:

1. hdb_catalog.hdb_scheduled_events: Table that stores all the scheduled events.
2. hdb_catalog.hdb_scheduled_event_invocation_logs: Table that stores all the HTTP requests and their responses of the scheduled events invocations.

Option 1: Clear only HTTP logs

1. Cron event invocation logs

DELETE FROM hdb_catalog.hdb_cron_event_invocation_logs;

2. Scheduled event invocation logs

DELETE FROM hdb_catalog.hdb_scheduled_event_invocation_logs;

Option 2: Clear processed events

1. Cron events

DELETE FROM hdb_catalog.hdb_cron_events
WHERE status IN ('delivered', 'error', 'dead');

2. Scheduled events

DELETE FROM hdb_catalog.hdb_scheduled_events
WHERE status IN ('delivered', 'error', 'dead');

Note

Deleting a cron/scheduled event will also delete the invocations related to that event.

Warning

The below options will clear all events including yet to be delivered events. If the cron trigger exists in the metadata, then new events will be generated automatically by the graphql-engine, but this step can take upto a minute.

Option 3: Clear all data for a particular cron trigger only

DELETE FROM hdb_catalog.hdb_cron_events
WHERE trigger_name = '<trigger_name>';

Option 4: Clear everything

1. Cron triggers

DELETE FROM hdb_catalog.hdb_cron_events;

2. Scheduled events

DELETE FROM hdb_catalog.hdb_scheduled_events;

Clearing data before a particular time period

If you wish to keep recent data and only clear data before a particular time period you can add the following time clause to your query's where clause:

-- units can be 'minutes', 'hours', 'days', 'months', 'years'
scheduled_time < now() - interval '<x> <units>'

For example: to delete all processed events and HTTP logs older than 3 months:

1. Cron triggers

DELETE FROM hdb_catalog.hdb_cron_events
WHERE status IN ('delivered', 'error', 'dead')
  AND scheduled_time < now() - interval '3 months';

2. Scheduled events

DELETE FROM hdb_catalog.hdb_scheduled_events
WHERE status IN ('delivered', 'error', 'dead')
 AND scheduled_time < now() - interval '3 months';

See the Postgres date/time functions for more details.