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
to it, so that we say we will do the wrapping just once right here
in _execute_context() / _execute_default(). An adjustment is made
to _handle_dbapi_error() to not assume self.__connection in case
we are already in an invalidated state
further adjustment to
0639c199a5, 41e7253dee, #3266
: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
take effect in all engine connection use cases, including
when user-custom connect routines are used via the
:paramref:`.create_engine.creator` parameter, as well as when
the :class:`.Connection` encounters a connection error on
revalidation.
fixes#3266
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
:class:`.CheckConstraint` associated with a :class:`.Boolean`
or :class:`.Enum` type object would be doubled in the target table.
The copy process now tracks the production of this constraint object
as local to a type object.
fixes#3260
mapped columns are re-mapped to
match column names as well as grouping of columns; in particular,
this allows columns that are explicitly grouped in a same-column-named
joined inheritance scenario to be mapped in the same way in the
history mappings, avoiding warnings added in the 0.9 series
regarding this pattern and allowing the same view of attribute
keys.
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
improved in conjunction with loader directives such as
:func:`.joinedload` and :func:`.contains_eager` such that if
two :meth:`.PropComparator.of_type` modifiers of the same
base type/path are encountered, they will be joined together
into a single "polymorphic" entity, rather than replacing
the entity of type A with the one of type B. E.g.
a joinedload of ``A.b.of_type(BSub1)->BSub1.c`` combined with
joinedload of ``A.b.of_type(BSub2)->BSub2.c`` will create a
single joinedload of ``A.b.of_type((BSub1, BSub2)) -> BSub1.c, BSub2.c``,
without the need for the ``with_polymorphic`` to be explicit
in the query.
fixes#3256
example, where the subclasses of AddressAssociation were not being
mapped as "single table inheritance", leading to problems when trying
to use the mappings further.
non-recommended use case of replacing a relationship on a fixed
mapped class many times, referring to an arbitrarily growing number of
target mappers. A warning is emitted when the old relationship is
replaced, however if the mapping were already used for querying, the
old relationship would still be referenced within some registries.
fixes#3251
INSERT, either through the values clause or as a "from select",
would pollute the column types used in the result set produced by
the RETURNING clause when columns from both statements shared the
same name, leading to potential errors or mis-adaptation when
retrieving the returning rows.
fixes#3248
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.
anonymous bound parameter names within expressions, to match the
existing use of this value as the key when rendered in an INSERT
or UPDATE statement. This allows :attr:`.Column.key` to be used
as a "substitute" string to work around a difficult column name
that doesn't translate well into a bound parameter name. Note that
the paramstyle is configurable on :func:`.create_engine` in any case,
and most DBAPIs today support a named and positional style.
fixes#3245