The five columns must appear in each mutable table and must have the column types described above.
Every row must have a unique RID value assigned at creation time and this value must not be recycled for use by another row in the same table.
Every row must have an immutable RCT time set during row creation.
Every tuple must have an RMT set during tuple creation. The RMT value must be equal to or greater than the RCT and every previously visible RMT for the same RID in the same table.
The RCB and RMB values must be comparable to the client ID space exposed by webauthn as the id field of the object returned from GET /authn/session. A NULL value may be present to indicate unknown provenance, e.g. for rows manipulated by server-side logic. However, a DBA may also substitute a distinct client ID representing an administrator or robot identity in such cases.
These system-managed columns have enforced policies described below.