Task 3 of the Phase 2 plan. Mirrors OperationTrackingSchema: the sf_messages
DDL, the four additive ALTERs, the last_attempt_at_ms backfill and the due-index
move verbatim into a static sync Apply(SqliteConnection), depending only on
Microsoft.Data.Sqlite. The Host needs to apply this to a LocalDb-managed
connection before RegisterReplicated installs the capture triggers; the store
still calls it so a directly-constructed store stays self-sufficient.
Two deviations from the plan as written, both deliberate:
1. The PRAGMA journal_mode=WAL in InitializeAsync STAYS. The plan's Step 4
snippet drops it, but Task 4 explicitly says not to move the equivalent
pragma ("LocalDb owns the connection's pragmas") — the two tasks contradict
each other. Keeping it preserves behaviour for the intermediate commits and
for directly-constructed stores; it becomes moot in Task 5 when the store
stops opening its own connections. Dropping it now would quietly regress the
concurrent-writer support the pragma's own comment documents.
2. Added a second test beyond the plan's. The specified test asserts only
against a freshly-created table, where CREATE TABLE already lists all 16
columns — it would pass with every ALTER deleted. The added test starts from
the pre-upgrade 12-column shape with a row in it and proves the upgrade path
runs and preserves data.
That second test also surfaced that the backfill lands 1 ms low: julianday()'s
double day-fraction cannot represent every millisecond. Pre-existing behaviour,
carried over verbatim, asserted with a 1 ms tolerance rather than pinning a
precision the implementation never had.
Suite: 154 passed, 0 failed.
Claude-Session: https://claude.ai/code/session_01BL2Vu1ESDQ9SCN4gVKkdts
Joseph Doherty
9e3239c5d9