VARBINARY(max) for large text/binary types.  The MSSQL dialect will
now respect this based on version detection, as well as the new
``deprecate_large_types`` flag.
fixes #3039

:class:`.sqlite.TIME`,
or :class:`.sqlite.DATETIME` types, and given a ``storage_format`` that
only renders numbers, will render the types in DDL as
``DATE_CHAR``, ``TIME_CHAR``, and ``DATETIME_CHAR``, so that despite the
lack of alpha characters in the values, the column will still
deliver the "text affinity".  Normally this is not needed, as the
textual values within the default storage formats already
imply text.
fixes #3257

Patch courtesy Gabor Gombas.
fixes #3127

to the aliasing syntax, as well as a new CTE feature
:meth:`.CTE.suffix_with`, which is useful for adding in special
Oracle-specific directives to the CTE.
fixes #3220

and Pymysql under Python 2.   This refers to the SQL statements
themselves, not the parameters, and affects issues such as table
and column names using non-ASCII characters.   These drivers both
appear to support Python 2 Unicode objects without issue in modern
versions.
fixes #3121

return type is not strictly assumed to be boolean; it now
returns a :class:`.Boolean` subclass called :class:`.MatchType`.
The type will still produce boolean behavior when used in Python
expressions, however the dialect can override its behavior at
result time.  In the case of MySQL, while the MATCH operator
is typically used in a boolean context within an expression,
if one actually queries for the value of a match expression, a
floating point value is returned; this value is not compatible
with SQLAlchemy's C-based boolean processor, so MySQL's result-set
behavior now follows that of the :class:`.Float` type.
A new operator object ``notmatch_op`` is also added to better allow
dialects to define the negation of a match operation.
fixes #3263

``pg_catalog.pg_table_is_visible(c.oid)``, rather than testing
for an exact schema match, when the schema name is None; this
so that the method will also illustrate that temporary tables
are present.  Note that this is a behavioral change, as Postgresql
allows a non-temporary table to silently overwrite an existing
temporary table of the same name, so this changes the behavior
of ``checkfirst`` in that unusual scenario.
fixes #3264

collection has been made consistent; this attribute is now a
:class:`.ColumnCollection` like that of all other constraints and
is initialized at the point when the constraint is associated with
a :class:`.Table`.
fixes #3243

for psycopg2 and others, encourage users to take advantage of positional
styles by documenting "paramstyle".   A section is added to psycopg2
specifically as this is a pretty common spot for named parameters
that may be unusually named.  fixes #3246.