Module « sqlalchemy.orm »

Classe « Mapped »

Informations générales

Héritage

            builtins.object
                Generic
    builtins.object
        HasMemoized
    builtins.object
        HasCacheKey
            MemoizedHasCacheKey
        builtins.object
            Immutable
builtins.object
    SQLRole
        StructuralRole
    builtins.object
        AllowsLambdaRole
            OnClauseRole
builtins.object
    SQLRole
        StructuralRole
    builtins.object
        UsesInspection
    builtins.object
        AllowsLambdaRole
            JoinTargetRole
        builtins.object
            HasCopyInternals
builtins.object
    Operators
        ColumnOperators
            PropComparator
        builtins.object
            InspectionAttr
        builtins.object
            _MappedAttribute
                QueryableAttribute
                    Mapped

Définition

class Mapped(QueryableAttribute, Generic):

Description _{[extrait de Mapped.__doc__]}

Represent an ORM mapped :term:`descriptor` attribute for typing purposes.

    This class represents the complete descriptor interface for any class
    attribute that will have been :term:`instrumented` by the ORM
    :class:`_orm.Mapper` class. When used with typing stubs, it is the final
    type that would be used by a type checker such as mypy to provide the full
    behavioral contract for the attribute.

    .. tip::

        The :class:`_orm.Mapped` class represents attributes that are handled
        directly by the :class:`_orm.Mapper` class. It does not include other
        Python descriptor classes that are provided as extensions, including
        :ref:`hybrids_toplevel` and the :ref:`associationproxy_toplevel`.
        While these systems still make use of ORM-specific superclasses
        and structures, they are not :term:`instrumented` by the
        :class:`_orm.Mapper` and instead provide their own functionality
        when they are accessed on a class.

    When using the :ref:`SQLAlchemy Mypy plugin <mypy_toplevel>`, the
    :class:`_orm.Mapped` construct is used in typing annotations to indicate to
    the plugin those attributes that are expected to be mapped; the plugin also
    applies :class:`_orm.Mapped` as an annotation automatically when it scans
    through declarative mappings in :ref:`orm_declarative_table` style. For
    more indirect mapping styles such as
    :ref:`imperative table <orm_imperative_table_configuration>` it is
    typically applied explicitly to class level attributes that expect
    to be mapped based on a given :class:`_schema.Table` configuration.

    :class:`_orm.Mapped` is defined in the
    `sqlalchemy2-stubs <https://pypi.org/project/sqlalchemy2-stubs>`_ project
    as a :pep:`484` generic class which may subscribe to any arbitrary Python
    type, which represents the Python type handled by the attribute::

        class MyMappedClass(Base):
            __table_ = Table(
                "some_table", Base.metadata,
                Column("id", Integer, primary_key=True),
                Column("data", String(50)),
                Column("created_at", DateTime)
            )

            id : Mapped[int]
            data: Mapped[str]
            created_at: Mapped[datetime]

    For complete background on how to use :class:`_orm.Mapped` with
    pep-484 tools like Mypy, see the link below for background on SQLAlchemy's
    Mypy plugin.

    .. versionadded:: 1.4

    .. seealso::

        :ref:`mypy_toplevel` - complete background on Mypy integration

    

Constructeur(s)

Signature du constructeur	Description
__init__(self, class_, key, parententity, impl=None, comparator=None, of_type=None, extra_criteria=())

Attributs statiques hérités de la classe PropComparator

prop

Propriétés héritées de la classe PropComparator

info

Liste des opérateurs

Opérateurs hérités de la classe ColumnOperators

__add__, __contains__, __eq__, __ge__, __getitem__, __gt__, __le__, __lshift__, __lt__, __mod__, __mul__, __ne__, __neg__, __radd__, __rmod__, __rmul__, __rshift__, __rsub__, __rtruediv__, __sub__, __truediv__

Liste des opérateurs

Opérateurs hérités de la classe Operators

__and__, __invert__, __or__

Méthodes héritées de la classe Generic

__class_getitem__, __init_subclass__, __subclasshook__

Méthodes héritées de la classe QueryableAttribute

__clause_element__, __getattr__, __reduce__, __str__, adapt_to_entity, and_, get_history, hasparent, label, of_type, operate, reverse_operate

Méthodes héritées de la classe HasMemoized

memoized_attribute, memoized_instancemethod

Méthodes héritées de la classe Immutable

params, unique_params

Méthodes héritées de la classe PropComparator

any, any_op, has, has_op, of_type_op

Méthodes héritées de la classe ColumnOperators

__div__, __rdiv__, all_, any_, asc, between, collate, concat, contains, desc, distinct, endswith, ilike, in_, is_, is_distinct_from, is_not, is_not_distinct_from, isnot, isnot_distinct_from, like, match, not_ilike, not_in, not_like, notilike, notin_, notlike, nulls_first, nulls_last, nullsfirst, nullslast, regexp_match, regexp_replace, startswith

Méthodes héritées de la classe Operators

bool_op, op

Méthodes héritées de la classe object

__delattr__, __dir__, __format__, __getattribute__, __hash__, __reduce_ex__, __repr__, __setattr__, __sizeof__