mysql.py 文件源码

def __init__(self, name, column_name, schema=None,
                 newname=None,
                 type_=None,
                 nullable=None,
                 default=False,
                 autoincrement=None):
        super(AlterColumn, self).__init__(name, schema=schema)
        self.column_name = column_name
        self.nullable = nullable
        self.newname = newname
        self.default = default
        self.autoincrement = autoincrement
        if type_ is None:
            raise util.CommandError(
                "All MySQL CHANGE/MODIFY COLUMN operations "
                "require the existing type."
            )

        self.type_ = sqltypes.to_instance(type_)