Why the 'SELF_REFERENCE_FROM_TRIGGER' error occurs from Apex triggers

Summary

The SELF_REFERENCE_FROM_TRIGGER error occurs when an Apex DML operation conflicts with an already-in-progress DML event on the same record. This article covers two common patterns that cause this error.

Direct DML Operations That Cause SELF_REFERENCE_FROM_TRIGGER

A direct operation occurs when:

1. A trigger performs a DML operation that attempts to update a record that is already being updated by another trigger. For more information, see DML Operations in Apex.
2. An Apex trigger causes a DML event to run on a record already involved in an identical DML event.

Indirect Operations That Cause SELF_REFERENCE_FROM_TRIGGER

An indirect operation occurs when a chain of automation creates a conflicting update. For example:

1. A request is submitted to update Object A.
2. A before-update trigger on Object A creates an Object B.
3. Object A is updated.
4. An after-insert trigger on Object B queries Object A and updates it.

In this scenario, Object A is being updated indirectly via the trigger chain. This generates the SELF_REFERENCE_FROM_TRIGGER error because Object A is already mid-transaction.