feat: option lab

backend/services/database.py

@@ -6645,8 +6645,21 @@ def get_snapshot_rows_asof(symbol: Optional[str] = None, as_of: Optional[str] =
     """One row per (symbol, expiry_date, strike, option_type) — the freshest capture at or
     before `as_of` (an ISO datetime string), or simply the freshest capture overall when
     as_of is omitted. Powers the Saxo History page's default 'current chain' view and its
-    'replay a past moment' filter — the full granular history stays in the table underneath
-    for later backtest use, this just picks one row per contract."""
+    'replay a past moment' filter, and services.option_chain.get_chain_slice's `as_of`
+    historical reconstruction (Portfolio retrospective comparison, Options Lab pricing
+    check) — the full granular history stays in the table underneath for later backtest
+    use, this just picks one row per contract.
+
+    A bare date (no time component, e.g. "2026-07-21") is treated as the END of that day,
+    not the start. `created_at` is always a real capture timestamp like
+    "2026-07-21 13:59:43" — comparing that against the bare string "2026-07-21" with SQL's
+    `<=` is a plain string comparison, and a 19-char timestamp always sorts AFTER its own
+    10-char date prefix, so every row captured that day would be silently excluded and a
+    date that genuinely has data would look like it has none (this was a real bug: querying
+    `as_of="2026-07-21"` against a symbol with rows *starting* on 2026-07-21 returned empty).
+    """
+    if as_of and len(as_of) <= 10:
+        as_of = as_of + "T23:59:59"
     conn = get_conn()
     where_symbol = "AND symbol = ?" if symbol else ""
     where_asof = "AND created_at <= ?" if as_of else ""