Asp.net 仅选择SQL Server 2014中通过表继承实现的表列的名称

我有一个问题，关于在SQL Server 2014中仅选择表继承实现的表列的名称

也就是说，有四种类型的人（学生、教师、员工和主管），所有这些人都包含从

人员

表继承的每种类型人员的

id

，以及必须选择和显示的姓名

表

TypePerson

：

CREATE TABLE [TypesPerson] 
(
    [typePersonID] INT NOT NULL,
    [typePerson] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_TypesPerson] PRIMARY KEY CLUSTERED ([typePersonID] ASC)
);

CREATE TABLE [Person] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] INT NOT NULL,
    CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])
);

CREATE TABLE [Students] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 1 PERSISTED, --type person = 1
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Students] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Teachers] 
(
    [PersonID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 2 PERSISTED, --type person = 2
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Teachers ] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Teachers ] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Employers] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 3 PERSISTED, --type person = 3
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Employers] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Employers] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

为人员类型插入

：

INSERT INTO [TypesPerson]
    SELECT 1,'students' UNION ALL
    SELECT 2,'teachers' UNION ALL
    SELECT 3,'employer' UNION ALL
    SELECT 4,'supervisor' 

表

人员

：

CREATE TABLE [TypesPerson] 
(
    [typePersonID] INT NOT NULL,
    [typePerson] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_TypesPerson] PRIMARY KEY CLUSTERED ([typePersonID] ASC)
);

CREATE TABLE [Person] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] INT NOT NULL,
    CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])
);

CREATE TABLE [Students] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 1 PERSISTED, --type person = 1
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Students] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Teachers] 
(
    [PersonID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 2 PERSISTED, --type person = 2
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Teachers ] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Teachers ] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Employers] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 3 PERSISTED, --type person = 3
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Employers] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Employers] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

表

学生

扩展

人

：

CREATE TABLE [TypesPerson] 
(
    [typePersonID] INT NOT NULL,
    [typePerson] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_TypesPerson] PRIMARY KEY CLUSTERED ([typePersonID] ASC)
);

CREATE TABLE [Person] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] INT NOT NULL,
    CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])
);

CREATE TABLE [Students] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 1 PERSISTED, --type person = 1
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Students] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Teachers] 
(
    [PersonID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 2 PERSISTED, --type person = 2
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Teachers ] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Teachers ] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Employers] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 3 PERSISTED, --type person = 3
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Employers] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Employers] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

表

教师

扩展

人员

：

CREATE TABLE [TypesPerson] 
(
    [typePersonID] INT NOT NULL,
    [typePerson] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_TypesPerson] PRIMARY KEY CLUSTERED ([typePersonID] ASC)
);

CREATE TABLE [Person] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] INT NOT NULL,
    CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])
);

CREATE TABLE [Students] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 1 PERSISTED, --type person = 1
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Students] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Teachers] 
(
    [PersonID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 2 PERSISTED, --type person = 2
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Teachers ] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Teachers ] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Employers] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 3 PERSISTED, --type person = 3
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Employers] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Employers] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

表

雇主

扩展

人员

：

CREATE TABLE [TypesPerson] 
(
    [typePersonID] INT NOT NULL,
    [typePerson] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_TypesPerson] PRIMARY KEY CLUSTERED ([typePersonID] ASC)
);

CREATE TABLE [Person] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] INT NOT NULL,
    CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])
);

CREATE TABLE [Students] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 1 PERSISTED, --type person = 1
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Students] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Teachers] 
(
    [PersonID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 2 PERSISTED, --type person = 2
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Teachers ] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Teachers ] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

CREATE TABLE [Employers] 
(
    [personID] INT IDENTITY (1, 1) NOT NULL ,
    [typePersonID] AS 3 PERSISTED, --type person = 3
    [name] VARCHAR(50) NOT NULL,
    CONSTRAINT [PK_Employers] PRIMARY KEY CLUSTERED ([PersonID] ASC),
    CONSTRAINT [FK_Employers] FOREIGN KEY ([typePersonID])
    REFERENCES [Person] ([typePersonID]),
);

插入数据以创建具有以下类型的人员：

INSERT INTO [Person] ([typePersonID]) VALUES (1); --students
INSERT INTO [Person] ([typePersonID]) VALUES (2); --teachers
INSERT INTO [Person] ([typePersonID]) VALUES (3); --employer
INSERT INTO [Person] ([typePersonID]) VALUES (4); --supervisor

插入数据以创建学生、教师和雇主：

INSERT INTO [Students]  ([name])  VALUES ('John'); --students
INSERT INTO [Teachers]  ([name])  VALUES ('Robert'); --teachers
INSERT INTO [Employers] ([name])  VALUES ('Ciara'); --employer
INSERT INTO [Supervisor] ([name]) VALUES ('Renata'); --supervisor

当我使用此脚本仅选择名称时

SELECT st.name, ts.name, es.name,  sp.name
FROM Person p
INNER JOIN Students   st ON p.personID= st.personID
INNER JOIN Teachers   ts ON p.personID= ts.personID
INNER JOIN Employers  es ON p.personID= es.personID
INNER JOIN Supervisor sp ON p.personID= sp.personID;

结果是


当我使用

有什么建议吗？
尝试以下方法时，您会感到惊讶：

SELECT t.typePerson, sp.name
FROM Person p
INNER JOIN [TypesPerson] as t ON p.[typePersonID] = t.[typePersonID]
INNER JOIN Supervisor sp ON p.personID= sp.personID;

问题是您有两个问题：

1.重复数据：
typePersonID
为同一个人存储两次。

2.
Person
中的
personID
与其他表中的
personID
没有任何关联

本质上，最好只有一个
Person
表，只需在其中添加name列即可。它会解决你所有的问题

而且,代替

CONSTRAINT [PK_UN_Person_Type] UNIQUE ([typePersonID])

放

通过使用
Pivot
您可以实现您的结果。但用简单的方法你可以试试

SELECT st.name Name
FROM Person p
INNER JOIN Students   st ON p.personID= st.personID

union
SELECT  ts.name Name
FROM Person p
INNER JOIN Teachers   ts ON p.personID= ts.personID
union

SELECT  es.name Name
FROM Person p
INNER JOIN Employers  es ON p.personID= es.personID
union

SELECT   sp.name Name
FROM Person p
INNER JOIN Supervisor sp ON p.personID= sp.personID

你必须使用unpivot。您的
Person
表设计允许最多插入4行，每种“类型的人”一行。@AlexKudryashev，我不这样说，因为它有很多问题的代码，我发现Adityathanks的答案很有价值，而且它的工作非常完美，列表视图水平显示所有姓名，