Delete raw events on a schedule

How to do it

Set the period in the privacy policy and in one setting. Hosted tools have a setting for it, such as Google Analytics 4's choice of 2 or 14 months. For your own store, drop old partitions as Expire warehouse data by partition describes. Build daily aggregates without IDs first, so long-term charts keep working. Include experiment exposure logs and the rejects table. The general rule is delete old data automatically. Record the period in Keep one retention schedule.

Examples

SQL example

-- PostgreSQL: events partitioned by month; the job detaches and drops partitions past the limit
ALTER TABLE events DETACH PARTITION events_2025_07;
DROP TABLE events_2025_07;

JavaScript example

const RETENTION_MONTHS = 14;
export async function dropExpiredPartitions(now = new Date()) {
  const cutoff = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth() - RETENTION_MONTHS, 1));
  for (const partition of await db.eventPartitionsBefore(cutoff)) await db.dropPartition(partition);
}

Python example

from datetime import date

RETENTION_MONTHS = 14

def drop_expired_partitions(today: date):
    months = today.year * 12 + today.month - 1 - RETENTION_MONTHS
    cutoff = date(months // 12, months % 12 + 1, 1)
    for partition in db.event_partitions_before(cutoff):
        db.drop_partition(partition)

How to check

A query finds no raw event older than the stated period. The aggregate table still has rows from before it, and none of them hold an ID.

Sources

• GDPR Article 5 on principles of processing

Related rules

• DEN-26 Expire warehouse data by partition in Data engineering
• DAT-31 Delete old data automatically in Data and databases
• CMP-11 Keep one retention schedule in Compliance and governance