The Gateway backend's gaps against SqlServer/QuestDb were documented
piecemeal. The backend-selection table in docs/Historian.md now also covers
the aggregate set (and the native time-weighted opt-in), emulated reverse
and end-only reads, the client-side events cap, retention and the health
probe.
Continuous historization on Gateway silently loses sample quality (stored
Good), comms-loss outage markers and non-numeric values. Building its live
writer, which only happens when ContinuousHistorization is enabled, now
logs one startup Warning that names the gaps and the alternatives.
The review asked for the matrix in the AdminUI backend picker, but no such
picker exists: the backend is configuration-only. Filed as a follow-up.
Rebased from the unpushed remed/lane-H2 branch (originally authored 2026-10-22
in session_01Ub9hGmYLQvn9XETzw7CMsT) onto current master.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Joseph Doherty
096a3d5b3c