diff --git a/db/zm_update-1.31.37.sql b/db/zm_update-1.31.37.sql
new file mode 100644
index 000000000..0d66e0282
--- /dev/null
+++ b/db/zm_update-1.31.37.sql
@@ -0,0 +1,49 @@
+DROP PROCEDURE IF EXISTS update_storage_stats;
+
+DELIMITER //
+
+CREATE PROCEDURE update_storage_stats(IN StorageId smallint(5), IN space BIGINT)
+
+sql security invoker
+
+deterministic
+
+begin
+
+    update Storage set DiskSpace = COALESCE(DiskSpace,0) + COALESCE(space,0) where Id = StorageId;
+
+end;
+
+//
+
+DROP TRIGGER IF EXISTS event_delete_trigger//
+
+CREATE TRIGGER event_delete_trigger BEFORE DELETE ON Events
+FOR EACH ROW
+  BEGIN
+    IF ( OLD.DiskSpace ) THEN
+      call update_storage_stats(OLD.StorageId, -OLD.DiskSpace);
+    END IF;
+    DELETE FROM Events_Hour WHERE EventId=OLD.Id;
+    DELETE FROM Events_Day WHERE EventId=OLD.Id;
+    DELETE FROM Events_Week WHERE EventId=OLD.Id;
+    DELETE FROM Events_Month WHERE EventId=OLD.Id;
+    IF ( OLD.Archived ) THEN
+      DELETE FROM Events_Archived WHERE EventId=OLD.Id;
+      UPDATE Monitors SET
+      ArchivedEvents = ArchivedEvents - 1,
+      ArchivedEventDiskSpace = COALESCE(ArchivedEventDiskSpace,0) - COALESCE(OLD.DiskSpace,0),
+      TotalEvents = TotalEvents - 1,
+      TotalEventDiskSpace = COALESCE(TotalEventDiskSpace,0) - COALESCE(OLD.DiskSpace,0)
+      WHERE Id=OLD.MonitorId;
+    ELSE
+      UPDATE Monitors SET
+      TotalEvents = TotalEvents-1,
+      TotalEventDiskSpace=COALESCE(TotalEventDiskSpace,0)-COALESCE(OLD.DiskSpace,0)
+      WHERE Id=OLD.MonitorId;
+    END IF;
+  END;
+
+//
+
+UPDATE Storage SET DiskSpace=(SELECT SUM(DiskSpace) FROM Events WHERE StorageId=Storage.Id)//