diff --git a/lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse_base/storage_schemas/connection.py b/lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse_base/storage_schemas/connection.py
index 33c21d88d..6d8d4f5ce 100644
--- a/lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse_base/storage_schemas/connection.py
+++ b/lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse_base/storage_schemas/connection.py
@@ -22,4 +22,4 @@ class ConnectionClickHouseBaseDataStorageSchema(
     endpoint = ma_fields.String(required=False, allow_none=True, load_default=None, dump_default=None)
     cluster_name = ma_fields.String(required=False, allow_none=True, load_default=None, dump_default=None)
     max_execution_time = ma_fields.Integer(required=False, allow_none=True, load_default=None, dump_default=None)
-    readonly = ma_fields.Integer(required=False, allow_none=True, load_default=None, dump_default=2)
+    readonly = ma_fields.Integer(required=False, allow_none=True, load_default=2, dump_default=2)