feat(pchome): automate authorized sales acquisition

tests/test_import_service_sql_params.py

@@ -29,11 +29,23 @@ def test_daily_snapshot_delete_casts_text_date_column_on_postgres(monkeypatch):
 def test_daily_snapshot_delete_query_uses_snapshot_date_cast_helper():
     source = Path("services/import_service.py").read_text(encoding="utf-8")
 
-    assert 'snapshot_date_expr = _date_filter_expr("snapshot_date")' in source
-    assert "DELETE FROM {table_name} WHERE {snapshot_date_expr} IN" in source
+    assert 'snapshot_expr = _date_filter_expr("snapshot_date")' in source
+    assert "f\"WHERE {snapshot_expr} IN ({snapshot_placeholders})\"" in source
     assert "DELETE FROM daily_sales_snapshot WHERE snapshot_date IN" not in source
 
 
+def test_sales_table_replacement_uses_one_transaction_connection():
+    source = Path("services/import_service.py").read_text(encoding="utf-8")
+    start = source.index("def _replace_sales_tables_atomic")
+    end = source.index("# 資料庫設定", start)
+    block = source[start:end]
+
+    assert "with engine.begin() as conn:" in block
+    assert 'df.to_sql(\n            "daily_sales_snapshot",\n            conn,' in block
+    assert 'df_monthly.to_sql(\n            "realtime_sales_monthly",\n            conn,' in block
+    assert "conn.commit()" not in block
+
+
 def test_daily_snapshot_delete_uses_iso_dates_on_sqlite(monkeypatch):
     monkeypatch.setattr(import_service, "_db_dialect_name", lambda: "sqlite")