diff options
Diffstat (limited to 'lib/sqlalchemy/schema.py')
| -rw-r--r-- | lib/sqlalchemy/schema.py | 161 |
1 files changed, 90 insertions, 71 deletions
diff --git a/lib/sqlalchemy/schema.py b/lib/sqlalchemy/schema.py index 00a21a30a..3dee2a0ba 100644 --- a/lib/sqlalchemy/schema.py +++ b/lib/sqlalchemy/schema.py @@ -840,61 +840,64 @@ class ForeignKey(SchemaItem): Column("remote_id", ForeignKey("main_table.id")) ) - For a composite (multiple column) FOREIGN KEY, use a :class:`ForeignKeyConstraint` - object specified at the level of the :class:`Table`. + For a composite (multiple column) FOREIGN KEY, use a + :class:`ForeignKeyConstraint` object specified at the level of the + :class:`Table`. - Further examples of foreign key configuration are in :ref:`metadata_foreignkeys`. + Further examples of foreign key configuration are in + :ref:`metadata_foreignkeys`. """ __visit_name__ = 'foreign_key' - def __init__(self, column, constraint=None, use_alter=False, name=None, onupdate=None, - ondelete=None, deferrable=None, initially=None, link_to_name=False): + def __init__(self, column, _constraint=None, use_alter=False, name=None, + onupdate=None, ondelete=None, deferrable=None, + initially=None, link_to_name=False): """ Construct a column-level FOREIGN KEY. - The :class:`ForeignKey` object when constructed generates a :class:`ForeignKeyConstraint` - which is associated with the parent :class:`Table` object's collection of constraints. + The :class:`ForeignKey` object when constructed generates a + :class:`ForeignKeyConstraint` which is associated with the parent + :class:`Table` object's collection of constraints. - :param column: A single target column for the key relationship. A :class:`Column` - object or a column name as a string: ``tablename.columnkey`` or - ``schema.tablename.columnkey``. ``columnkey`` is the ``key`` which has been assigned - to the column (defaults to the column name itself), unless ``link_to_name`` is ``True`` - in which case the rendered name of the column is used. + :param column: A single target column for the key relationship. A + :class:`Column` object or a column name as a string: + ``tablename.columnkey`` or ``schema.tablename.columnkey``. + ``columnkey`` is the ``key`` which has been assigned to the column + (defaults to the column name itself), unless ``link_to_name`` is + ``True`` in which case the rendered name of the column is used. - :param constraint: Optional. A parent :class:`ForeignKeyConstraint` object. If not - supplied, a :class:`ForeignKeyConstraint` will be automatically created - and added to the parent table. + :param name: Optional string. An in-database name for the key if + `constraint` is not provided. - :param name: Optional string. An in-database name for the key if `constraint` is - not provided. + :param onupdate: Optional string. If set, emit ON UPDATE <value> when + issuing DDL for this constraint. Typical values include CASCADE, + DELETE and RESTRICT. - :param onupdate: Optional string. If set, emit ON UPDATE <value> when issuing DDL - for this constraint. Typical values include CASCADE, DELETE and - RESTRICT. + :param ondelete: Optional string. If set, emit ON DELETE <value> when + issuing DDL for this constraint. Typical values include CASCADE, + DELETE and RESTRICT. - :param ondelete: Optional string. If set, emit ON DELETE <value> when issuing DDL - for this constraint. Typical values include CASCADE, DELETE and - RESTRICT. + :param deferrable: Optional bool. If set, emit DEFERRABLE or NOT + DEFERRABLE when issuing DDL for this constraint. - :param deferrable: Optional bool. If set, emit DEFERRABLE or NOT DEFERRABLE when - issuing DDL for this constraint. - - :param initially: Optional string. If set, emit INITIALLY <value> when issuing DDL - for this constraint. + :param initially: Optional string. If set, emit INITIALLY <value> when + issuing DDL for this constraint. - :param link_to_name: if True, the string name given in ``column`` is the rendered - name of the referenced column, not its locally assigned ``key``. + :param link_to_name: if True, the string name given in ``column`` is + the rendered name of the referenced column, not its locally assigned + ``key``. - :param use_alter: passed to the underlying :class:`ForeignKeyConstraint` to indicate the - constraint should be generated/dropped externally from the CREATE TABLE/ - DROP TABLE statement. See that classes' constructor for details. + :param use_alter: passed to the underlying + :class:`ForeignKeyConstraint` to indicate the constraint should be + generated/dropped externally from the CREATE TABLE/ DROP TABLE + statement. See that classes' constructor for details. """ self._colspec = column - self.constraint = constraint + self.constraint = _constraint self.use_alter = use_alter self.name = name self.onupdate = onupdate @@ -909,7 +912,16 @@ class ForeignKey(SchemaItem): def copy(self, schema=None): """Produce a copy of this ForeignKey object.""" - return ForeignKey(self._get_colspec(schema=schema)) + return ForeignKey( + self._get_colspec(schema=schema), + use_alter=self.use_alter, + name=self.name, + onupdate=self.onupdate, + ondelete=self.ondelete, + deferrable=self.deferrable, + initially=self.initially, + link_to_name=self.link_to_name + ) def _get_colspec(self, schema=None): if schema: @@ -1394,52 +1406,56 @@ class ForeignKeyConstraint(Constraint): Defines a single column or composite FOREIGN KEY ... REFERENCES constraint. For a no-frills, single column foreign key, adding a - :class:`ForeignKey` to the definition of a :class:`Column` is a shorthand equivalent - for an unnamed, single column :class:`ForeignKeyConstraint`. + :class:`ForeignKey` to the definition of a :class:`Column` is a shorthand + equivalent for an unnamed, single column :class:`ForeignKeyConstraint`. Examples of foreign key configuration are in :ref:`metadata_foreignkeys`. """ __visit_name__ = 'foreign_key_constraint' - def __init__(self, columns, refcolumns, name=None, onupdate=None, ondelete=None, - deferrable=None, initially=None, use_alter=False, link_to_name=False, table=None): + def __init__(self, columns, refcolumns, name=None, onupdate=None, + ondelete=None, deferrable=None, initially=None, use_alter=False, + link_to_name=False, table=None): """Construct a composite-capable FOREIGN KEY. - :param columns: A sequence of local column names. The named columns must be defined - and present in the parent Table. The names should match the ``key`` given - to each column (defaults to the name) unless ``link_to_name`` is True. + :param columns: A sequence of local column names. The named columns + must be defined and present in the parent Table. The names should + match the ``key`` given to each column (defaults to the name) unless + ``link_to_name`` is True. - :param refcolumns: A sequence of foreign column names or Column objects. The columns - must all be located within the same Table. + :param refcolumns: A sequence of foreign column names or Column + objects. The columns must all be located within the same Table. :param name: Optional, the in-database name of the key. - :param onupdate: Optional string. If set, emit ON UPDATE <value> when issuing DDL - for this constraint. Typical values include CASCADE, DELETE and - RESTRICT. - - :param ondelete: Optional string. If set, emit ON DELETE <value> when issuing DDL - for this constraint. Typical values include CASCADE, DELETE and - RESTRICT. - - :param deferrable: Optional bool. If set, emit DEFERRABLE or NOT DEFERRABLE when - issuing DDL for this constraint. - - :param initially: Optional string. If set, emit INITIALLY <value> when issuing DDL - for this constraint. - - :param link_to_name: if True, the string name given in ``column`` is the rendered - name of the referenced column, not its locally assigned ``key``. - - :param use_alter: If True, do not emit the DDL for this constraint - as part of the CREATE TABLE definition. Instead, generate it via an - ALTER TABLE statement issued after the full collection of tables have been - created, and drop it via an ALTER TABLE statement before the full collection - of tables are dropped. This is shorthand for the usage of - :class:`AddConstraint` and :class:`DropConstraint` applied as "after-create" - and "before-drop" events on the MetaData object. This is normally used to - generate/drop constraints on objects that are mutually dependent on each other. + :param onupdate: Optional string. If set, emit ON UPDATE <value> when + issuing DDL for this constraint. Typical values include CASCADE, + DELETE and RESTRICT. + + :param ondelete: Optional string. If set, emit ON DELETE <value> when + issuing DDL for this constraint. Typical values include CASCADE, + DELETE and RESTRICT. + + :param deferrable: Optional bool. If set, emit DEFERRABLE or NOT + DEFERRABLE when issuing DDL for this constraint. + + :param initially: Optional string. If set, emit INITIALLY <value> when + issuing DDL for this constraint. + + :param link_to_name: if True, the string name given in ``column`` is + the rendered name of the referenced column, not its locally assigned + ``key``. + + :param use_alter: If True, do not emit the DDL for this constraint as + part of the CREATE TABLE definition. Instead, generate it via an ALTER + TABLE statement issued after the full collection of tables have been + created, and drop it via an ALTER TABLE statement before the full + collection of tables are dropped. This is shorthand for the usage of + :class:`AddConstraint` and :class:`DropConstraint` applied as + "after-create" and "before-drop" events on the MetaData object. This + is normally used to generate/drop constraints on objects that are + mutually dependent on each other. """ super(ForeignKeyConstraint, self).__init__(name, deferrable, initially) @@ -1455,7 +1471,7 @@ class ForeignKeyConstraint(Constraint): for col, refcol in zip(columns, refcolumns): self._elements[col] = ForeignKey( refcol, - constraint=self, + _constraint=self, name=self.name, onupdate=self.onupdate, ondelete=self.ondelete, @@ -1494,7 +1510,10 @@ class ForeignKeyConstraint(Constraint): name=self.name, onupdate=self.onupdate, ondelete=self.ondelete, - use_alter=self.use_alter + use_alter=self.use_alter, + deferrable=self.deferrable, + initially=self.initially, + link_to_name=self.link_to_name ) class PrimaryKeyConstraint(ColumnCollectionConstraint): |