Clean up event data¶

Introduction¶

Hasura stores event data associated with Event Triggers in the `hdb_catalog` schema of the database containing the source table.

If there are lots of events, the metadata 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.

Tables involved¶

Event Triggers have 2 tables managed by Hasura:

1. hdb_catalog.event_log: This is the table that stores all captured events.
2. hdb_catalog.event_invocation_logs: This is that table that stores all HTTP requests and responses.

Option 1: Clear only HTTP logs¶

DELETE FROM hdb_catalog.event_invocation_logs;

Option 2: Clear only processed events¶

DELETE FROM hdb_catalog.event_log
WHERE delivered = true OR error = true;

Option 3: Clear all processed events and HTTP logs¶

This is the combination of Option 1 and Option 2.

DELETE FROM hdb_catalog.event_invocation_logs;

DELETE FROM hdb_catalog.event_log
WHERE delivered = true OR error = true;

Option 4: Clear all event data for a particular event trigger only¶

DELETE FROM
hdb_catalog.event_invocation_logs
WHERE event_id IN (
    SELECT id FROM hdb_catalog.event_log
    WHERE trigger_name = '<event_trigger_name>' );

DELETE FROM
hdb_catalog.event_log
WHERE trigger_name = '<event_trigger_name>'
AND (delivered = true OR error = true);

Option 5: Clear everything¶

DELETE FROM hdb_catalog.event_invocation_logs;

DELETE FROM hdb_catalog.event_log;

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'
created_at < now() - interval '<x> <units>'

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

DELETE FROM hdb_catalog.event_invocation_logs
WHERE created_at < now() - interval '3 months';

DELETE FROM hdb_catalog.event_log
WHERE (delivered = true OR error = true)
 AND created_at < now() - interval '3 months';

See the Postgres date/time functions for more details.