diff --git a/api/s30_scada_device_data.py b/api/s30_scada_device_data.py
index b1f74b3..e09b813 100644
--- a/api/s30_scada_device_data.py
+++ b/api/s30_scada_device_data.py
@@ -38,17 +38,14 @@ def set_scada_device_data_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
         f_time, f_value = f"'{time}'", value
         undo_sql += f"\ninsert into scada_device_data (device_id, time, value) values ({f_device_id}, {f_time}, {f_value});"
 
-    redo_cs = { 'type': 'scada_device_data' } | new
-    undo_cs = { 'type': 'scada_device_data' } | old
+    redo_cs = g_update_prefix | { 'type': 'scada_device_data' } | new
+    undo_cs = g_update_prefix | { 'type': 'scada_device_data' } | old
 
     return DbChangeSet(redo_sql, undo_sql, [redo_cs], [undo_cs])
 
 
 def set_scada_device_data(name: str, cs: ChangeSet) -> ChangeSet:
-    result = set_scada_device_data_cmd(name, cs)
-    result.redo_cs[0] |= g_update_prefix
-    result.undo_cs[0] |= g_update_prefix
-    return execute_command(name, result)
+    return execute_command(name, set_scada_device_data_cmd(name, cs))
 
 
 def add_scada_device_data_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
@@ -96,7 +93,7 @@ def delete_scada_device_data(name: str, cs: ChangeSet) -> ChangeSet:
 def clean_scada_device_data_cmd(name: str) -> ChangeSet:
     cs = ChangeSet()
 
-    rows = read_all(name, 'select distinct device_id from scada_device_data')
+    rows = read_all(name, 'select distinct device_id from scada_device_data acs')
     for row in rows:
         cs.update({ 'type': 'scada_device_data', 'device_id': row['device_id'], 'data': [] })