实体框架外键表未保存对其BindingSource所做的更改

CREATE TABLE `Vehicles` (
    `ID` int(10) unsigned NOT NULL AUTO_INCREMENT,
    ... Other columns
    PRIMARY KEY (`ID`)
    ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=latin1

以及:

CREATE TABLE `VehicleOptions` (
    `ID` int(10) unsigned NOT NULL AUTO_INCREMENT,
    `VehicleID` int(10) unsigned NOT NULL,
    ... Other columns
    PRIMARY KEY (`ID`),
    KEY `FK_Vehicles_to_VehicleOptions` (`VehicleID`),
    CONSTRAINT `FK_Vehicles_to_VehicleOptions` FOREIGN KEY (`VehicleID`) REFERENCES `vehicles` (`ID`) ON DELETE CASCADE ON UPDATE NO ACTION
    ) ENGINE=InnoDB DEFAULT CHARSET=latin1

以下是数据对象的图片:

我把一辆又一辆的车辆拖到我的表格上。然后使用LINQ查询加载数据库:

var dataSource = from v in Database.DataContext.Vehicles.Include("VehicleOptions")
                 orderby v.Stock descending
                 select v;

// The vehicles BindingSource
bsVehicles.DataSource = dataSource;

// The vehicleoptions BindingSource
bsVehicleOptions.DataSource = bsVehicles;
bsVehicleOptions.DataMember = "VehicleOptions";

每当我在表单上添加/编辑数据时,我都会调用:

bsVehicles.SuspendBinding();
bsVehicleOptions.SuspendBinding();
Database.DataContext.SaveChanges();
bsVehicleOptions.ResumeBinding();
bsVehicles.ResumeBinding();

对所做的更改 bsVehicles bsVehicleOptions 清空他们的数据 Database.DataContext.SaveChanges(); 我是不是漏了什么?

注意:我使用的是EntityFrameworkV4(我听说旧版本中的关联很时髦?)。