mappings unless you have taken the additional steps to make
this feasible**.
+ * The polymorphic identity WHERE criteria is **not** included
+ for single- or
+ joined- table updates - this must be added **manually** even
+ for single table inheritance.
+
* The method does **not** offer in-Python cascading of
relationships - it is assumed that ON DELETE CASCADE/SET
NULL/etc. is configured for any foreign key references
filter(Employee.name == 'dilbert').\\
update({"engineer_type": "programmer"})
+ * The polymorphic identity WHERE criteria is **not** included
+ for single- or
+ joined- table updates - this must be added **manually**, even
+ for single table inheritance.
+
* The :meth:`.MapperEvents.before_update` and
:meth:`.MapperEvents.after_update`
events **are not invoked from this method**. Instead, the