in callcounts specific to the "expiration" of objects, as in
the "auto expire" feature of :meth:`.Session.commit` and
for :meth:`.Session.expire_all`, as well as in the "cleanup" step
which occurs when object states are garbage collected.
fixes#3307
dialect on a type where MySQL does not support CAST; MySQL only
supports CAST on a subset of datatypes. SQLAlchemy has for a long
time just omitted the CAST for unsupported types in the case of
MySQL. While we don't want to change this now, we emit a warning
to show that it's taken place. A warning is also emitted when
a CAST is used with an older MySQL version (< 4) that doesn't support
CAST at all, it's skipped in this case as well.
fixes#3237
when using the :paramref:`.Column.server_default` parameter, will
now be rendered using the "inline" compiler, so that they are rendered
as-is, rather than as bound parameters.
fixes#3087
levels; :meth:`.Connection.get_isolation_level`,
:attr:`.Connection.default_isolation_level`.
- enhance documentation inter-linkage between new accessors,
existing isolation_level parameters, as well as in
the dialect-level methods which should be fully covered
by Engine/Connection level APIs now.
:meth:`.Session.get_bind` method when calling upon
:meth:`.Query.count`, :meth:`.Query.update`, :meth:`.Query.delete`,
as well as queries against mapped columns,
:obj:`.column_property` objects, and SQL functions and expressions
derived from mapped columns. This allows sessions that rely upon
either customized :meth:`.Session.get_bind` schemes or "bound" metadata
to work in all relevant cases.
fixes#3227fixes#3242fixes#1326
now be constructed such that the visit methods receive an indication
of the owning expression object, if any. Any visit method that
accepts keyword arguments (e.g. ``**kw``) will in most cases
receive a keyword argument ``type_expression``, referring to the
expression object that the type is contained within. For columns
in DDL, the dialect's compiler class may need to alter its
``get_column_specification()`` method to support this as well.
The ``UserDefinedType.get_col_spec()`` method will also receive
``type_expression`` if it provides ``**kw`` in its argument
signature.
fixes#3074
expression in an :class:`.Index` that did not correspond directly
to a table-bound column; typically when a :func:`.text` construct
was one of the expressions within the index; or could misinterpret the
list of expressions if one or more of them were such an expression.
fixes#3174
the :func:`.orm.load_only` option to cover all attributes not
explicitly mentioned, now takes into account the superclasses
of a given entity, if that entity is mapped with inheritance mapping,
so that attribute names within the superclasses are also omitted
from the load. Additionally, the polymorphic discriminator column
is unconditionally included in the list, just in the same way that
primary key columns are, so that even with load_only() set up,
polymorphic loading of subtypes continues to function correctly.
fixes#3287
repaired to work more usefully with tables that have Python-
side default values and/or functions, as well as server-side
defaults. The feature will now work with a dialect that uses
"positional" parameters; a Python callable will also be
invoked individually for each row just as is the case with an
"executemany" style invocation; a server- side default column
will no longer implicitly receive the value explicitly
specified for the first row, instead refusing to invoke
without an explicit value. fixes#3288
:class:`.Query` before it fetched results, particularly when
row processors can't be formed, the cursor would stay open with
results pending and not actually be closed. This is typically only
an issue on an interpreter like Pypy where the cursor isn't
immediately GC'ed, and can in some circumstances lead to transactions/
locks being open longer than is desirable.
fixes#3285
to start up listener collections; this pulls the overhead off of construction
and makes performance much like the descriptor version, while still allowing
slots. Fix up some profiles.
assume that the empty string, or a set with a single empty string
value, is in fact a set with a single empty string; instead, this
is by default treated as the empty set. In order to handle persistence
of a :class:`.mysql.SET` that actually wants to include the blank
value ``''`` as a legitimate value, a new bitwise operational mode
is added which is enabled by the
:paramref:`.mysql.SET.retrieve_as_bitwise` flag, which will persist
and retrieve values unambiguously using their bitflag positioning.
Storage and retrieval of unicode values for driver configurations
that aren't converting unicode natively is also repaired.
fixes#3283
sort_tables_and_constraints function.
- The DDL generation system of :meth:`.MetaData.create_all`
and :meth:`.Metadata.drop_all` has been enhanced to in most
cases automatically handle the case of mutually dependent
foreign key constraints; the need for the
:paramref:`.ForeignKeyConstraint.use_alter` flag is greatly
reduced. The system also works for constraints which aren't given
a name up front; only in the case of DROP is a name required for
at least one of the constraints involved in the cycle.
fixes#3282
a type that was also a :class:`.TypeDecorator` would fail with
Python's "Cannot create a consistent method resolution order (MRO)"
error, when any kind of SQL comparison expression were used against
an object using this type.
and regexp parsing of SQL in order to form a complete picture of
constraints + their names. fixes#3244fixes#3261
- factor various PRAGMA work to be centralized into one call
to :meth:`.Session.close`, except also calls
:meth:`.Connection.invalidate`
on all connections, guaranteeing that they will not be returned to
the connection pool. This is useful in situations e.g. dealing
with gevent timeouts when it is not safe to use the connection further,
even for rollbacks.
references #3258
Mike Bayer