User creation occurs in one of four ways.
- In an "autocreate" log event, the user is automatically created, e.g. by Extension:CentralAuth.
- In a "byemail" log event, the created user receives its password by email.
- In a "create" log event, an anonymous user creates an account for themself.
- In a "create2" log event, a logged in user creates an account for someone else.
logging.log_params contains a "4::userid" field with the user.user_id of the created account.
API:Logevents puts the user ID of the created account in the "userid" property and does not reveal the user ID of the user creating the account.