As discussed in T353953: Don't use actor IDs for private CheckUser events when these actions are performed by IP addresses, IP addresses cannot acquire an actor ID when temporary accounts are enabled. However, we still need to associate certain private CheckUser events (such as failed login attempts) with an IP address performer.
To do this, it has been decided to make the cupe_actor column nullable. Using 0 was considered, but if a third-party wiki uses foreign key constraints, then using 0 would cause a constraint violation whereas NULL does not. I would also argue that using NULL is clearer than 0 from a non MediaWIki context.
Acceptance criteria
- Modify the cupe_actor column to be nullable (a separate task will be filed to apply this change to WMF wikis at a later stage).
QA Results - VC
| AC | Status | Details |
|---|---|---|
| 1 | ✅ | https://phabricator.wikimedia.org/T359873 here |
