add note that schema translate not supported per object

Fixes: #7832
Change-Id: I241e4cbd1b5d6df46e49e29e4ab1cac021f2895c

diff --git a/doc/build/core/connections.rst b/doc/build/core/connections.rst
index 2e188e20e67ca159cccadf6f2fba2f7cfd918533..f749dbe4a35fdcb07dff47eaf1f4799e9dd48658 100644 (file)
--- a/doc/build/core/connections.rst
+++ b/doc/build/core/connections.rst
@@ -757,6 +757,14 @@ as the schema name is passed to these methods explicitly.
 
       session = Session(schema_engine)
 
+  When using the ORM, the schema translate feature is only supported as
+  **a single schema translate map per Session**.   It will **not work** if
+  different schema translate maps are given on a per-statement basis, as
+  the ORM :class:`_orm.Session` does not take current schema translate
+  values into account for individual objects.  In other words, all
+  objects loaded in a particular :class:`_orm.Session` must be based on the
+  **same** ``schema_translate_map``.
+
       ...