by contains_eager() out of individual instance states.
[ticket:1553]
+ - Fixed a needless select which would occur when merging
+ transient objects that contained a null primary key
+ identifier. [ticket:1618]
+
- Mutable collection passed to the "extension" attribute
of relation(), column_property() etc. will not be mutated
or shared among multiple instrumentation calls, preventing
data from the "subclass" table of the parent.
[ticket:1485]
- - Fixed a needless select which would occur when merging
- transient objects that contained a null primary key
- identifier. [ticket:1618]
-
- relations() now have greater ability to be "overridden",
meaning a subclass that explicitly specifies a relation()
overriding that of the parent class will be honored