diff --git a/learnware/market/database_ops.py b/learnware/market/database_ops.py
index 38679c7..1306260 100644
--- a/learnware/market/database_ops.py
+++ b/learnware/market/database_ops.py
@@ -58,7 +58,7 @@ class DatabaseOperations(object):
             # it is postgresql
             dbname_start = url.rfind("/")
             dbname = url[dbname_start+1:]
-            url_no_dbname = url[:dbname_start]
+            url_no_dbname = url[:dbname_start] + "/postgres"
             engine = create_engine(url_no_dbname)
 
             with engine.connect() as conn: