sqlalchemy.sql.type_api.Variant

class documentation

class Variant(TypeDecorator[_T]): (source)

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deprecated. symbol is present for backwards-compatibility with workaround recipes, however this actual type should not be used.

Method __init__ Construct a :class:`.TypeDecorator`.

Inherited from TypeDecorator:

Class Comparator A :class:`.TypeEngine.Comparator` that is specific to :class:`.TypeDecorator`.
Method __getattr__ Proxy all other undefined accessors to the underlying implementation.
Method __repr__ Undocumented
Method bind_expression Given a bind value (i.e. a :class:`.BindParameter` instance), return a SQL expression which will typically wrap the given parameter.
Method bind_processor Provide a bound value processing function for the given :class:`.Dialect`.
Method coerce_compared_value Suggest a type for a 'coerced' Python value in an expression.
Method column_expression Given a SELECT column expression, return a wrapping SQL expression.
Method compare_values Given two values, compare them for equality.
Method copy Produce a copy of this :class:`.TypeDecorator` instance.
Method get_dbapi_type Return the DBAPI type object represented by this :class:`.TypeDecorator`.
Method literal_processor Provide a literal processing function for the given :class:`.Dialect`.
Method load_dialect_impl Return a :class:`.TypeEngine` object corresponding to a dialect.
Method process_bind_param Receive a bound parameter value to be converted.
Method process_literal_param Receive a literal parameter value to be rendered inline within a statement.
Method process_result_value Receive a result-row column value to be converted.
Method result_processor Provide a result value processing function for the given :class:`.Dialect`.
Method type_engine Return a dialect-specific :class:`.TypeEngine` instance for this :class:`.TypeDecorator`.
Class Variable __visit_name__ Undocumented
Class Variable coerce_to_is_types Specify those Python types which should be coerced at the expression level to "IS <constant>" when compared using ``==`` (and same for ``IS NOT`` in conjunction with ``!=``).
Instance Variable impl Undocumented
Property comparator_factory Undocumented
Property impl_instance Undocumented
Property sort_key_function A sorting function that can be passed as the key to sorted.
Method _gen_dialect_impl Undocumented
Method _set_parent Support SchemaEventTarget
Method _set_parent_with_dispatch Support SchemaEventTarget
Method _unwrapped_dialect_impl Return the 'unwrapped' dialect impl for this type.
Class Variable _is_type_decorator Undocumented
Property _has_bind_expression memoized boolean, check if bind_expression is implemented.
Property _has_bind_processor memoized boolean, check if process_bind_param is implemented.
Property _has_column_expression memoized boolean, check if column_expression is implemented.
Property _has_literal_processor memoized boolean, check if process_literal_param is implemented.
Property _has_result_processor memoized boolean, check if process_result_value is implemented.
Property _type_affinity Return a rudimental 'affinity' value expressing the general class of type.

Inherited from SchemaEventTarget (via TypeDecorator):

Class Variable dispatch Undocumented

Inherited from EventTarget (via TypeDecorator, SchemaEventTarget):

Class Variable __slots__ Undocumented

Inherited from ExternalType (via TypeDecorator, SchemaEventTarget, EventTarget):

Class Variable cache_ok Indicate if statements using this :class:`.ExternalType` are "safe to cache".
Property _static_cache_key Undocumented

Inherited from TypeEngineMixin (via TypeDecorator, SchemaEventTarget, EventTarget, ExternalType):

Method adapt Undocumented
Method dialect_impl Undocumented

Inherited from TypeEngine (via TypeDecorator, SchemaEventTarget, EventTarget, ExternalType, TypeEngineMixin):

Method __str__ Undocumented
Method as_generic Return an instance of the generic type corresponding to this type using heuristic rule. The method may be overridden if this heuristic rule is not sufficient.
Method compare_against_backend Compare this type against the given backend type.
Method compile Produce a string-compiled form of this :class:`.TypeEngine`.
Method copy_value Undocumented
Method evaluates_none Return a copy of this type which has the :attr:`.should_evaluate_none` flag set to True.
Method with_variant Produce a copy of this type object that will utilize the given type when applied to the dialect of the given name.
Class Variable hashable Flag, if False, means values from this type aren't hashable.
Class Variable render_bind_cast Render bind casts for :attr:`.BindTyping.RENDER_CASTS` mode.
Class Variable render_literal_cast render casts when rendering a value as an inline literal, e.g. with :meth:`.TypeEngine.literal_processor`.
Class Variable should_evaluate_none If True, the Python constant ``None`` is considered to be handled explicitly by this type.
Property python_type Return the Python type object expected to be returned by instances of this type, if known.
Static Method _to_instance Undocumented
Method _cached_bind_processor Return a dialect-specific bind processor for this type.
Method _cached_custom_processor return a dialect-specific processing object for custom purposes.
Method _cached_literal_processor Return a dialect-specific literal processor for this type.
Method _cached_result_processor Return a dialect-specific result processor for this type.
Method _compare_type_affinity Undocumented
Method _default_dialect Undocumented
Method _dialect_info Return a dialect-specific registry which caches a dialect-specific implementation, bind processing function, and one or more result processing functions.
Method _resolve_for_literal adjust this type given a literal Python value that will be stored in a bound parameter.
Method _resolve_for_python_type given a Python type (e.g. ``int``, ``str``, etc. ) return an instance of this :class:`.TypeEngine` that's appropriate for this type.
Class Variable _is_array Undocumented
Class Variable _is_table_value Undocumented
Class Variable _is_tuple_type Undocumented
Class Variable _isnull Undocumented
Class Variable _sqla_type Undocumented
Property _generic_type_affinity Undocumented

Inherited from Visitable (via TypeDecorator, SchemaEventTarget, EventTarget, ExternalType, TypeEngineMixin, TypeEngine):

Method __class_getitem__ Undocumented
Method __init_subclass__ Undocumented
Class Method _generate_compiler_dispatch Undocumented
Method _compiler_dispatch Undocumented
Class Variable _original_compiler_dispatch Undocumented
def __init__(self, *arg: Any, **kw: Any): (source)
overrides sqlalchemy.sql.type_api.TypeDecorator.__init__

Construct a :class:`.TypeDecorator`. Arguments sent here are passed to the constructor of the class assigned to the ``impl`` class level attribute, assuming the ``impl`` is a callable, and the resulting object is assigned to the ``self.impl`` instance attribute (thus overriding the class attribute of the same name). If the class level ``impl`` is not a callable (the unusual case), it will be assigned to the same instance attribute 'as-is', ignoring those arguments passed to the constructor. Subclasses can override this to customize the generation of ``self.impl`` entirely.