从SQL中的多个表级联删除行

Question

I've got two tables with the following structure:

Person

• Id
• Name

Class

• Id
• PersonId
• Sequence

and some data:

Person

1   name1
2   name2
3   name3

Class

1   1   3
2   1   1
3   1   2
4   2   1

Class table can contain multiple rows related to one row from Person . PersonId from Class table is foreign key to Id in Person table. I'd like to delete data related to Person with Id 1, so remove the 3 rows from Class , and 1 row from Person using one query.

How can I do that in SQL?

Answer 1

Try This:

CREATE TABLE [dbo].[Class](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [PersonId] [int] NULL,
    [Sequence] [int] NULL,
 CONSTRAINT [PK_Class] PRIMARY KEY CLUSTERED 
(
    [Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO
/****** Object:  Table [dbo].[Person]    Script Date: 26-05-2014 07:54:26 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Person](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [Person] [nchar](10) NULL,
 CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED 
(
    [Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO
ALTER TABLE [dbo].[Class]  WITH CHECK ADD  CONSTRAINT [FK_Class_Person] FOREIGN KEY([PersonId])
REFERENCES [dbo].[Person] ([Id])
ON DELETE CASCADE
GO
ALTER TABLE [dbo].[Class] CHECK CONSTRAINT [FK_Class_Person]
GO