Method _copy

lib/sqlalchemy/sql/schema.py:2737–2805

Create a copy of this ``Column``, uninitialized. This is used in :meth:`_schema.Table.to_metadata` and by the ORM.

(self, **kw: Any)

        return self._copy(**kw)

    def _copy(self, **kw: Any) -> Column[Any]:
        """Create a copy of this ``Column``, uninitialized.

        This is used in :meth:`_schema.Table.to_metadata` and by the ORM.

        """

        # Constraint objects plus non-constraint-bound ForeignKey objects
        args: List[SchemaItem] = [
            c._copy(**kw) for c in self.constraints if not c._type_bound
        ] + [c._copy(**kw) for c in self.foreign_keys if not c.constraint]

        # ticket #5276
        column_kwargs = {}
        for dialect_name in self.dialect_options:
            dialect_options = self.dialect_options[dialect_name]._non_defaults
            for (
                dialect_option_key,
                dialect_option_value,
            ) in dialect_options.items():
                column_kwargs[dialect_name + "_" + dialect_option_key] = (
                    dialect_option_value
                )

        server_default = self.server_default
        server_onupdate = self.server_onupdate
        if isinstance(server_default, (Computed, Identity)):
            # TODO: likely should be copied in all cases
            # TODO: if a Sequence, we would need to transfer the Sequence
            # .metadata as well
            args.append(server_default._copy(**kw))
            server_default = server_onupdate = None

        type_ = self.type
        if isinstance(type_, SchemaEventTarget):
            type_ = type_.copy(**kw)

        # TODO: DefaultGenerator is not copied here!  it's just used again
        # with _set_parent() pointing to the old column.  see the new
        # use of _copy() in the new _merge() method

        c = self._constructor(
            name=self.name,
            type_=type_,
            key=self.key,
            primary_key=self.primary_key,
            unique=self.unique,
            system=self.system,
            # quote=self.quote,  # disabled 2013-08-27 (commit 031ef080)
            index=self.index,
            autoincrement=self.autoincrement,
            default=self.default,
            server_default=server_default,
            onupdate=self.onupdate,
            server_onupdate=server_onupdate,
            doc=self.doc,
            comment=self.comment,
            _omit_from_statements=self._omit_from_statements,