加速當日業績 metadata 查詢

routes/daily_sales_routes.py

@@ -202,6 +202,43 @@ def _get_available_daily_dates(engine, table_name='daily_sales_snapshot'):
     return dates
 
 
+def _get_daily_sales_metadata(engine, table_name='daily_sales_snapshot'):
+    """一次取得日期選單與資料指紋，避免首屏每次掃兩輪 daily snapshot。"""
+    validate_table_name(table_name)
+    if engine.dialect.name != 'postgresql':
+        return (
+            _get_available_daily_dates(engine, table_name),
+            _get_data_fingerprint(engine, table_name),
+        )
+
+    query = text(
+        f'SELECT MAX(snapshot_date)::text AS max_snapshot_date, '
+        f'COUNT(*) AS row_count, '
+        f'ARRAY_AGG(DISTINCT snapshot_date::date ORDER BY snapshot_date::date DESC) '
+        f'FILTER (WHERE snapshot_date IS NOT NULL) AS available_dates '
+        f'FROM "{table_name}"'
+    )
+    try:
+        with engine.connect() as conn:
+            row = conn.execute(query).fetchone()
+        if not row:
+            return [], (None, 0)
+        raw_dates = row[2] or []
+        dates = []
+        for raw_date in raw_dates:
+            try:
+                dates.append(pd.to_datetime(raw_date).normalize())
+            except Exception:
+                continue
+        return dates, (row[0], row[1] or 0)
+    except Exception as exc:
+        sys_log.warning(f"[DailySales] metadata 查詢失敗，改用相容查詢: {exc}")
+        return (
+            _get_available_daily_dates(engine, table_name),
+            _get_data_fingerprint(engine, table_name),
+        )
+
+
 def _read_daily_sales_window(engine, table_name, start_date, end_date):
     """只讀取畫面需要的日期窗口，降低冷 worker 首頁等待時間。"""
     return safe_read_sql(
@@ -501,7 +538,7 @@ def daily_sales():
                                    chart_data=None, categories=None, calendar_data=None, selected_month=None,
                                    datetime_now=datetime_now_str, active_page='daily_sales')
 
-        available_dates = _get_available_daily_dates(engine, table_name)
+        available_dates, current_fingerprint = _get_daily_sales_metadata(engine, table_name)
         if not available_dates:
             return render_template('daily_sales.html',
                                    error="資料表為空，請先匯入當日業績資料。",
@@ -537,7 +574,6 @@ def daily_sales():
         )
         data_end = max(selected_date, month_end)
 
-        current_fingerprint = _get_data_fingerprint(engine, table_name)
         view_cache_key = "|".join([
             table_name,
             'view',