diff --git a/product/ERP5Type/tests/custom_zodb.py b/product/ERP5Type/tests/custom_zodb.py
index e94fefa6d22dcc4ee0e3eb4754ca16de641f2ac4..4914157a7e84843d11dfe1e78a442a4d675b2049 100644
--- a/product/ERP5Type/tests/custom_zodb.py
+++ b/product/ERP5Type/tests/custom_zodb.py
@@ -47,7 +47,8 @@ if save_mysql:
     command = 'mysqldump %s > %s' % (getMySQLArguments(), dump_sql_path,)
     if verbosity:
       _print('Dumping MySQL database with %s...' % command)
-    os.system(command)
+    ret = os.system(command)
+    assert not ret
 
 _print("Cleaning static files ... ")
 for static_dir in static_dir_list: