have been enhanced such that the function handler is now capable
of raising or returning a new exception object, which will replace
the exception normally being thrown by SQLAlchemy.
fixes #3076

primary key change within a savepoint block would not
participate in being restored to their former state (not in
session, in session, previous PK) after the outer transaction
were rolled back. fixes #3108

as the attribute and probably just replaced itself, so that is
now _set_enable_single_crit
- as a side effect of the main issue fixed here, correct the case in
adjust_for_single_inheritance where the same mapper appears more
than once in mapper_adapter_map; run through a set() for uniqueness.
- Fixed bug in subquery eager loading in conjunction with
:func:`.with_polymorphic`, the targeting of entities and columns
in the subquery load has been made more accurate with respect
to this type of entity and others. Fixes #3106

system, whereby using a :class:`.TypeDecorator` in conjunction with
variant would fail with an MRO error when a comparison operator was used.
fixes #3102

ProgrammingError, not OperationalError, in modern MySQL-Python versions;
all MySQL error codes that are tested for "is disconnect" are now
checked within OperationalError and ProgrammingError regardless.
fixes #3101

of :ticket:`3060` from verision 0.9.5.  A self-referential relationship
with lazy='dynamic' would raise a TypeError within a flush operation.
fixes #3099

distinguished for when it was actually the value ``False``.
The ``__abstract__`` flag needs to acutally evaluate to a True
value at the level being tested.
fixes #3097