C# “错误”；逐级删除“；

我有问题。我需要在约束[FK_SumaRoute_Suma]中添加“级联删除on”：

CREATE TABLE [dbo].[SumaRoute] (
    [Id]      INT IDENTITY (1, 1) NOT NULL,
    [SumaId]  INT NOT NULL,
    [RouteId] INT NOT NULL,
    CONSTRAINT [PK_SumaRoute] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_SumaRoute_Suma] FOREIGN KEY ([SumaId]) REFERENCES [dbo].[Suma] ([Id])  ***** HERE !!! *****,
    CONSTRAINT [FK_SumaRoute_Route] FOREIGN KEY ([RouteId]) REFERENCES [dbo].[Route] ([Id]) ON DELETE CASCADE
);

但是SQL Server返回错误：

正在创建FK_零件集。。。 （104,1）：SQL72014:.Net SqlClient数据提供程序：
味精1785，第16级，状态0，第1行
在表“Part”上引入外键约束“FK_Part_Suma1”可能会导致循环或多个级联路径。指定“删除不操作”或“更新不操作”，或修改其他外键约束。
（104,1）：SQL72014:.Net SqlClient数据提供程序：
Msg 1750，第16级，第0状态，第1行
无法创建约束或索引。请参阅前面的错误。
执行批处理时出错

我的桌子：

CREATE TABLE [dbo].[Suma] (
    [Id]       INT           IDENTITY (1, 1) NOT NULL,
    [SumaName] NVARCHAR (50) NOT NULL,
    CONSTRAINT [PK_Suma_1] PRIMARY KEY CLUSTERED ([Id] ASC)
);
CREATE TABLE [dbo].[Route] (
    [Id]        INT           IDENTITY (1, 1) NOT NULL,
    [RouteName] NVARCHAR (50) NOT NULL,
    CONSTRAINT [PK_Route] PRIMARY KEY CLUSTERED ([Id] ASC)
);

编辑：下一个表格

CREATE TABLE [dbo].[Part] (
    [Id]       INT           IDENTITY (1, 1) NOT NULL,
    [PartName] NVARCHAR (50) NOT NULL,
    [SumaId]   INT           NOT NULL,
    [Place]    NVARCHAR (50) NULL,
    [Time]     TIME (7)      NULL,
    CONSTRAINT [PK_Part] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_Part_Suma1] FOREIGN KEY ([SumaId]) REFERENCES [dbo].[Suma] ([Id])
);
CREATE TABLE [dbo].[Order] (
    [Id]             INT      IDENTITY (1, 1) NOT NULL,
    [PartId]         INT      NOT NULL,
    [RouteId]        INT      NULL,
    [SumaId]         INT      NOT NULL,
    [DriverId]       INT      NULL,
    [Express]        BIT      CONSTRAINT [DF_Order_Express] DEFAULT ((0)) NOT NULL,
    [Status]         INT      CONSTRAINT [DF_Order_Status] DEFAULT ((0)) NOT NULL,
    [TimeLeft]       DATETIME NOT NULL,
    [StartTransport] DATETIME NULL,
    [Created]        DATETIME NULL,
    CONSTRAINT [PK_Order] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_Order_Part] FOREIGN KEY ([PartId]) REFERENCES [dbo].[Part] ([Id]) ON DELETE CASCADE,
    CONSTRAINT [FK_Order_Route] FOREIGN KEY ([RouteId]) REFERENCES [dbo].[Route] ([Id]) ON DELETE CASCADE,
    CONSTRAINT [FK_Order_Suma] FOREIGN KEY ([SumaId]) REFERENCES [dbo].[Suma] ([Id]) ON DELETE CASCADE,
    CONSTRAINT [FK_Order_User] FOREIGN KEY ([DriverId]) REFERENCES [dbo].[User] ([Id]) ON DELETE CASCADE
);
CREATE TABLE [dbo].[User] (
    [Id]            INT            IDENTITY (1, 1) NOT NULL,
    [Pin]           NCHAR (4)      NOT NULL,
    [SumaIdSigned]  INT            NULL,
    [RouteIdSigned] INT            NULL,
    [Name]          NVARCHAR (50)  NOT NULL,
    [Surname]       NVARCHAR (50)  NOT NULL,
    [Type]          BIT            NOT NULL,
    [TokenGCM]      NVARCHAR (400) NULL,
    [TokenAccess]   NVARCHAR (50)  NULL,
    [SignedTime]    DATETIME       NULL,
    CONSTRAINT [PK_User] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_User_Route] FOREIGN KEY ([RouteIdSigned]) REFERENCES [dbo].[Route] ([Id]),
    CONSTRAINT [FK_User_Suma] FOREIGN KEY ([SumaIdSigned]) REFERENCES [dbo].[Suma] ([Id])
);

我可以删除Suma、路由和用户。如果我删除Suma行（id=5）并且任何订单都包含SumaId（5），那么我需要使用SumaId（5）删除所有订单。

请问我在做什么？

---

对不起，我的英语：）

显然问题出在别处。错误消息是关于代码中未显示的

FK\u Part\u Suma1

。你能分享其他表格的信息吗？你显示的表格和参考资料是否完整？没有

Suma

，

Route

和

Part

外键到其他表？您问题中的架构不会有问题…编辑：这已完成