a column setup on the ABC base which had a different attribute
name vs. column name would not be correctly mapped on the final
base class.   The failure on 0.9 would be silent whereas on
1.0 it raised an ArgumentError, so may not have been noticed
prior to 1.0.
fixes #3480

"multiple parameter sets" there is a much more common case
which works equally well for INSERT/UPDATE/DELETE e.g.
executemany().   reference #3476

``__eq__()`` to return a non-boolean-capable object, such as
some geoalchemy types as well as numpy types, were being tested
for ``bool()`` during a unit of work update operation, where in
0.9 the return value of ``__eq__()`` was tested against "is True"
to guard against this.
fixes #3469

correctly if it were loaded within the "optimized inheritance load",
which is a special SELECT emitted in the case of joined table
inheritance used to populate expired or unloaded attributes against
a joined table without loading the base table.  This is related to
the fact that SQLA 1.0 no longer guesses about loading deferred
columns and must be directed explicitly.
fixes #3468

mapped attribute on top of an :func:`.aliased` object would
resolve to the original mapper, not the :func:`.aliased`
version of it, thereby causing problems for a :class:`.Query`
that relies on this attribute (e.g. it's the only representative
attribute given in the constructor) to figure out the correct FROM
clause for the query.
fixes #3466
- apply consitency to ._parententity vs.
__clause_element__()._annotations['parententity']
in terms of aliased class, test it all.

feature would cause an object's version counter to be incremented
when there was no net change to the object's row, but instead an object
related to it via relationship (e.g. typically many-to-one)
were associated or de-associated with it, resulting in an UPDATE
statement that updates the object's version counter and nothing else.
In the use case where the relatively recent "server side" and/or
"programmatic/conditional" version counter feature were used
(e.g. setting version_id_generator to False), the bug could cause an
UPDATE without a valid SET clause to be emitted.
fixes #3465

this is definitely something that is asked regularly.