sqlalchemy.orm.attributes.ScalarAttributeImpl

class documentation

class ScalarAttributeImpl(AttributeImpl): (source)

Known subclasses: sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

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represents a scalar value-holding InstrumentedAttribute.

Method __init__ Construct an AttributeImpl.
Method delete Undocumented
Method fire_remove_event Undocumented
Method fire_replace_event Undocumented
Method get_history Undocumented
Method set Undocumented
Class Variable __slots__ Undocumented
Class Variable collection Undocumented
Class Variable default_accepts_scalar_loader Undocumented
Class Variable dynamic Undocumented
Class Variable supports_population Undocumented
Class Variable uses_objects Undocumented
Instance Variable _append_token Undocumented
Instance Variable _remove_token Undocumented
Instance Variable _replace_token Undocumented

Inherited from AttributeImpl:

Method __str__ Undocumented
Method append Undocumented
Method get Retrieve a value from the given object. If a callable is assembled on this object's attribute, and passive is False, the callable will be executed and the resulting value will be set as the new value for this attribute.
Method get_all_pending Return a list of tuples of (state, obj) for all objects in this attribute's current state + history.
Method get_committed_value return the unchanged value of this attribute
Method hasparent Return the boolean value of a `hasparent` flag attached to the given state.
Method pop Undocumented
Method remove Undocumented
Method set_committed_value set an attribute value on the given instance and 'commit' it.
Method sethasparent Set a boolean flag on the given item corresponding to whether or not it is attached to a parent object via the attribute represented by this ``InstrumentedAttribute``.
Class Variable active_history Undocumented
Instance Variable accepts_scalar_loader Undocumented
Instance Variable callable_ Undocumented
Instance Variable class_ Undocumented
Instance Variable dispatch Undocumented
Instance Variable is_equal Undocumented
Instance Variable key Undocumented
Instance Variable load_on_unexpire Undocumented
Instance Variable parent_token Undocumented
Instance Variable send_modified_events Undocumented
Instance Variable trackparent Undocumented
Method _default_value Produce an empty value for an uninitialized scalar attribute.
Method _fire_loader_callables Undocumented
Method _get_active_history Backwards compat for impl.active_history
Method _set_active_history Undocumented
Class Variable _is_has_collection_adapter Undocumented
Instance Variable _deferred_history Undocumented
Instance Variable _modified_token Undocumented
def __init__(self, *arg, **kw): (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.__init__

Construct an AttributeImpl. :param \class_: associated class :param key: string name of the attribute :param \callable_: optional function which generates a callable based on a parent instance, which produces the "default" values for a scalar or collection attribute when it's first accessed, if not present already. :param trackparent: if True, attempt to track if an instance has a parent attached to it via this attribute. :param compare_function: a function that compares two values which are normally assignable to this attribute. :param active_history: indicates that get_history() should always return the "old" value, even if it means executing a lazy callable upon attribute change. :param parent_token: Usually references the MapperProperty, used as a key for the hasparent() function to identify an "owning" attribute. Allows multiple AttributeImpls to all match a single owner attribute. :param load_on_unexpire: if False, don't include this attribute in a load-on-expired operation, i.e. the "expired_attribute_loader" process. The attribute can still be in the "expired" list and be considered to be "expired". Previously, this flag was called "expire_missing" and is only used by a deferred column attribute. :param send_modified_events: if False, the InstanceState._modified_event method will have no effect; this means the attribute will never show up as changed in a history entry.

def delete(self, state: InstanceState[Any], dict_: _InstanceDict): (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.delete
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

def fire_remove_event(self, state: InstanceState[Any], dict_: _InstanceDict, value: Any, initiator: Optional[AttributeEventToken]): (source)
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

def fire_replace_event(self, state: InstanceState[Any], dict_: _InstanceDict, value: _T, previous: Any, initiator: Optional[AttributeEventToken]) -> _T: (source)
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

def get_history(self, state: InstanceState[Any], dict_: Dict[str, Any], passive: PassiveFlag = PASSIVE_OFF) -> History: (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.get_history
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

def set(self, state: InstanceState[Any], dict_: Dict[str, Any], value: Any, initiator: Optional[AttributeEventToken] = None, passive: PassiveFlag = PASSIVE_OFF, check_old: Optional[object] = None, pop: bool = False): (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.set
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

__slots__: tuple[str, ...] = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.__slots__
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

collection: bool = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.collection
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

default_accepts_scalar_loader: bool = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.default_accepts_scalar_loader
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

dynamic: bool = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.dynamic

Undocumented

supports_population: bool = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.supports_population
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

uses_objects: bool = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl.uses_objects
overridden in sqlalchemy.orm.attributes.ScalarObjectAttributeImpl

Undocumented

_append_token = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl._append_token

Undocumented

_remove_token = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl._remove_token

Undocumented

_replace_token = (source)
overrides sqlalchemy.orm.attributes.AttributeImpl._replace_token

Undocumented