sqlalchemy.sql.schema.Constraint

class documentation

class Constraint(DialectKWArgs, SchemaItem):

Known subclasses: sqlalchemy.sql.schema.ColumnCollectionConstraint

A table-level SQL constraint.

_schema.Constraint serves as the base class for the series of constraint objects that can be associated with _schema.Table objects, including _schema.PrimaryKeyConstraint, _schema.ForeignKeyConstraint _schema.UniqueConstraint, and _schema.CheckConstraint.

Method	`__init__`	Create a SQL constraint.
Method	`_copy`	Undocumented
Method	`_set_parent`	Associate with this SchemaEvent's parent object.
Method	`copy`	Undocumented
Class Variable	`__visit_name__`	Undocumented
Instance Variable	`_create_rule`	Undocumented
Instance Variable	`_type_bound`	Undocumented
Instance Variable	`deferrable`	Undocumented
Instance Variable	`info`	Info dictionary associated with the object, allowing user-defined data to be associated with this `.SchemaItem`.
Instance Variable	`initially`	Undocumented
Instance Variable	`name`	Undocumented
Instance Variable	`parent`	Undocumented
Property	`table`	Undocumented

Inherited from DialectKWArgs:

Class Method	`argument_for`	Add a new kind of dialect-specific keyword argument for this class.
Method	`_kw_reg_for_dialect_cls`	Undocumented
Method	`_validate_dialect_kwargs`	Undocumented
Class Variable	`_dialect_kwargs_traverse_internals`	Undocumented
Class Variable	`_kw_registry`	Undocumented
Property	`dialect_kwargs`	A collection of keyword arguments specified as dialect-specific options to this construct.
Property	`dialect_options`	A collection of keyword arguments specified as dialect-specific options to this construct.
Property	`kwargs`	A synonym for `.DialectKWArgs.dialect_kwargs`.

Inherited from SchemaItem:

Method	`__repr__`	Undocumented
Method	`_init_items`	Initialize the list of child items for this SchemaItem.
Method	`_schema_item_copy`	Undocumented
Class Variable	`_use_schema_map`	Undocumented
Class Variable	`create_drop_stringify_dialect`	Undocumented

Inherited from SchemaEventTarget (via SchemaItem):

Method _set_parent_with_dispatch Undocumented

Inherited from Traversible (via SchemaItem):

Method	`get_children`	Return immediate child `.visitors.Traversible` elements of this `.visitors.Traversible`.
Method	`__class_getitem__`	Undocumented

def __init__(self, name=None, deferrable=None, initially=None, _create_rule=None, info=None, _type_bound=False, **dialect_kw):

overridden in sqlalchemy.sql.schema.ColumnCollectionConstraint

Create a SQL constraint.

Parameters
name	Optional, the in-database name of this `Constraint`.
deferrable	Optional bool. If set, emit DEFERRABLE or NOT DEFERRABLE when issuing DDL for this constraint.
initially	Optional string. If set, emit INITIALLY <value> when issuing DDL for this constraint.
_create_rule	used internally by some datatypes that also create constraints.
info	Optional data dictionary which will be populated into the `.SchemaItem.info` attribute of this object. New in version 1.0.0.
_type_bound	used internally to indicate that this constraint is associated with a specific datatype.
**dialect_kw	Additional keyword arguments are dialect specific, and passed in the form `<dialectname>_<argname>`. See the documentation regarding an individual dialect at :ref:`dialect_toplevel` for detail on documented arguments.

def _copy(self, **kw):

overridden in sqlalchemy.sql.schema.ColumnCollectionConstraint

Undocumented

def _set_parent(self, parent, **kw):

overrides sqlalchemy.sql.base.SchemaEventTarget._set_parent

overridden in sqlalchemy.sql.schema.ColumnCollectionConstraint

Associate with this SchemaEvent's parent object.

@util.deprecated('1.4', 'The :meth:`_schema.Constraint.copy` method is deprecated and will be removed in a future release.')
def copy(self, **kw):

overridden in sqlalchemy.sql.schema.ColumnCollectionConstraint

Undocumented

__visit_name__: str =

overrides sqlalchemy.sql.schema.SchemaItem.__visit_name__

overridden in sqlalchemy.dialects.postgresql.ExcludeConstraint, sqlalchemy.sql.schema.CheckConstraint, sqlalchemy.sql.schema.ForeignKeyConstraint, sqlalchemy.sql.schema.PrimaryKeyConstraint, sqlalchemy.sql.schema.UniqueConstraint

Undocumented

_create_rule =

Undocumented

_type_bound =

Undocumented

deferrable =

Undocumented

info =

overrides sqlalchemy.sql.schema.SchemaItem.info

Info dictionary associated with the object, allowing user-defined data to be associated with this .SchemaItem.

The dictionary is automatically generated when first accessed. It can also be specified in the constructor of some objects, such as _schema.Table and _schema.Column.

initially =

Undocumented

name =

Undocumented

parent =

Undocumented

@property
table =

Undocumented