"auto increment" column has been changed, such that autoincrement
is no longer implicitly enabled for a :class:`.Table` that has a
composite primary key. In order to accommodate being able to enable
autoincrement for a composite PK member column while at the same time
maintaining SQLAlchemy's long standing behavior of enabling
implicit autoincrement for a single integer primary key, a third
state has been added to the :paramref:`.Column.autoincrement` parameter
``"auto"``, which is now the default. fixes#3216
- The MySQL dialect no longer generates an extra "KEY" directive when
generating CREATE TABLE DDL for a table using InnoDB with a
composite primary key with AUTO_INCREMENT on a column that isn't the
first column; to overcome InnoDB's limitation here, the PRIMARY KEY
constraint is now generated with the AUTO_INCREMENT column placed
first in the list of columns.
symbols with names quoted to force all-lower-case would not be
identified properly in reflection queries. The :class:`.quoted_name`
construct is now applied to incoming symbol names that detect as
forced into all-lower-case within the "name normalize" process.
fixes#3548
- repair the CREATE INDEX ddl for schemas
- update provisioning to include support for setting up ATTACH DATABASE up front
for the test_schema; enable "schemas" testing for SQLite
- changelog / migration notes for new SQLite schema support
- include the "schema" as the "remote_schema" when we reflect SQLite FKs
as part of 🎫`3424` to allow disabling of the MSSQL dialect's
attempts to create aliases for schema-qualified tables, now defaults
to False; the old behavior is now disabled unless explicitly turned on.
fixes#3434
which indicates to the ORM that a positive set of None should be
persisted as the value NULL, instead of omitting the column from
the INSERT statement. This feature is used both as part of the
implementation for 🎫`3514` as well as a standalone feature
available on any type. fixes#3250
- add new documentation section illustrating the "how to force null"
use case of #3250
- alter our change from #3514 so that the class-level flag is now
called "should_evaluate_none"; so that "evaluates_none" is now
a generative method.
to a :class:`.types.Enum` or :class:`.postgresql.ENUM` subtype
will now emit the expected "CREATE TYPE" and "DROP TYPE" DDL when
the type is used within a "CREATE TABLE" or "DROP TABLE".
fixes#2729
expression element which is late-evaluated at compile time. Previously,
the function was only a conversion function which would handle different
expression inputs by returning either a :class:`.Label` of a column-oriented
expression or a copy of a given :class:`.BindParameter` object,
which in particular prevented the operation from being logically
maintained when an ORM-level expression transformation would convert
a column to a bound parameter (e.g. for lazy loading).
fixes#3531
to use mapper.cascade_iterator() for this purpose as it was not really
designed for that use case. Add docs to cascade_iterator() pointing
to the recipe. fixes#3498
:meth:`.Session.bulk_save_objects` and related bulk methods have
been scaled back to the extent that this functionality is not
currently used, e.g. checks for column default values to be
fetched after an INSERT or UPDATE statement.
fixes#3526
column that had some kind of "fetch on update" value and was not
locally present in the given object would cause an AttributeError
within the operation.
fixes#3525
unambiguous tracking of all object lifecycle state transitions
in terms of the :class:`.Session` itself, e.g. pending,
transient, persistent, detached. The state of the object
within each event is also defined.
fixes#2677
- Added a new session lifecycle state :term:`deleted`. This new state
represents an object that has been deleted from the :term:`persistent`
state and will move to the :term:`detached` state once the transaction
is committed. This resolves the long-standing issue that objects
which were deleted existed in a gray area between persistent and
detached. The :attr:`.InstanceState.persistent` accessor will
**no longer** report on a deleted object as persistent; the
:attr:`.InstanceState.deleted` accessor will instead be True for
these objects, until they become detached.
- The :paramref:`.Session.weak_identity_map` parameter is deprecated.
See the new recipe at :ref:`session_referencing_behavior` for
an event-based approach to maintaining strong identity map behavior.
references #3517
insert statement, 🎫`3288`, where the column type for the
default-holding column would not be propagated to the compiled
statement in the case where the default was being used,
leading to bind-level type handlers not being invoked.
fixes#3520
with a :class:`.SchemaType` implementation, typically :class:`.Enum`
or :class:`.Boolean` with regards to ensuring that the per-table
events are propagated from the implementation type to the outer type.
These events are used
to ensure that the constraints or Postgresql types (e.g. ENUM)
are correctly created (and possibly dropped) along with the parent
table.
fixes#2919
all DBs now support ON UPDATE CASCADE other than Oracle, there's no need
to try to reimplement more functionality here and users should be encouraged
to forego natural PKs unless their target platform supports them.
references #2666
``<function> WITHIN GROUP (ORDER BY <criteria>)``, using the
method :class:`.FunctionElement.within_group`. A series of common
set-aggregate functions with return types derived from the set have
been added. This includes functions like :class:`.percentile_cont`,
:class:`.dense_rank` and others.
fixes#1370
- make sure we use func.name for all _literal_as_binds in functions.py
so we get consistent naming behavior for parameters.
which automatically returns an :class:`.Array` of the correct type
and supports index / slice operations. As arrays are only
supported on Postgresql at the moment, only actually works on
Postgresql. fixes#3132
refer mostly to the DDL object; this system is primarily useful
in that case, and not for built-in objects. Reference that
the built-in case is not really viable right now. References #3442.
- Fixes to the ORM and to the postgresql JSON type regarding the
``None`` constant in conjunction with the Postgresql :class:`.JSON` type. When
the :paramref:`.JSON.none_as_null` flag is left at its default
value of ``False``, the ORM will now correctly insert the Json
"'null'" string into the column whenever the value on the ORM
object is set to the value ``None`` or when the value ``None``
is used with :meth:`.Session.bulk_insert_mappings`,
**including** if the column has a default or server default on it. This
makes use of a new type-level flag "evaluates_none" which is implemented
by the JSON type based on the none_as_null flag. fixes#3514
- Added a new constant :attr:`.postgresql.JSON.NULL`, indicating
that the JSON NULL value should be used for a value
regardless of other settings. part of fixes#3514
- The "hashable" flag on special datatypes such as :class:`.postgresql.ARRAY`,
:class:`.postgresql.JSON` and :class:`.postgresql.HSTORE` is now
set to False, which allows these types to be fetchable in ORM
queries that include entities within the row. fixes#3499
- The Postgresql :class:`.postgresql.ARRAY` type now supports multidimensional
indexed access, e.g. expressions such as ``somecol[5][6]`` without
any need for explicit casts or type coercions, provided
that the :paramref:`.postgresql.ARRAY.dimensions` parameter is set to the
desired number of dimensions. fixes#3487
- The return type for the :class:`.postgresql.JSON` and :class:`.postgresql.JSONB`
when using indexed access has been fixed to work like Postgresql itself,
and returns an expression that itself is of type :class:`.postgresql.JSON`
or :class:`.postgresql.JSONB`. Previously, the accessor would return
:class:`.NullType` which disallowed subsequent JSON-like operators to be
used. part of fixes#3503
- The :class:`.postgresql.JSON`, :class:`.postgresql.JSONB` and
:class:`.postgresql.HSTORE` datatypes now allow full control over the
return type from an indexed textual access operation, either ``column[someindex].astext``
for a JSON type or ``column[someindex]`` for an HSTORE type,
via the :paramref:`.postgresql.JSON.astext_type` and
:paramref:`.postgresql.HSTORE.text_type` parameters. also part of fixes#3503
- The :attr:`.postgresql.JSON.Comparator.astext` modifier no longer
calls upon :meth:`.ColumnElement.cast` implicitly, as PG's JSON/JSONB
types allow cross-casting between each other as well. Code that
makes use of :meth:`.ColumnElement.cast` on JSON indexed access,
e.g. ``col[someindex].cast(Integer)``, will need to be changed
to call :attr:`.postgresql.JSON.Comparator.astext` explicitly. This is
part of the refactor in references #3503 for consistency in operator
use.
such as :meth:`.Query.union` now handle the case where the embedded
SELECT statements need to be parenthesized due to the fact that they
include LIMIT, OFFSET and/or ORDER BY. These queries **do not work
on SQLite**, and will fail on that backend as they did before, but
should now work on all other backends.
fixes#2528
to function for a many-to-one relationship. The loader used an
API to place "None" into the dictionary which no longer actually
writes a value; this is a side effect of 🎫`3061`.
- remove InstanceState._initialize() totally, it's used nowhere
else and no longer does what it says it does
- fill in fowards-port version ids throughout the changes for 1.0.9
without primary keys to be reflected as well as ensured that
a SQL statement involved in foreign key detection is pre-fetched up
front to avoid driver issues upon nested queries. Fixes here
courtesy Eugene Zapolsky; note that we cannot currently test
Sybase to locally verify these changes.
fixes#3508fixes#3509
or other variable-length column type with unbounded length
by assigning the token ``"max"`` to the
length attribute of the string. While using the ``"max"`` token
explicitly is supported by the SQL Server dialect, it isn't part
of the normal contract of the base string types, and instead the
length should just be left as None. The dialect now assigns the
length to None on reflection of the type so that the type behaves
normally in other contexts.
fixes#3504
up SQLAlchemy's version detection under Python 3 and inadvertently
not using the correct unicode mode for Python 3. This would cause
issues such as bound variables mis-interpreted as NULL and rows
silently not being returned.
fixes#3491
Mike Bayer