PRIMARY KEY

--自己总结了几种加PRIMARY KEY的发放

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[AA]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[AA]
GO

CREATE TABLE [dbo].[AA] (
[ID] [int] IDENTITY (1, 1) NOT NULL ,
[Name] [nvarchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NULL ,
[DOB] [datetime] NULL ,
[Score] [int] NULL
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[AA] ADD
CONSTRAINT [PK_AA] PRIMARY KEY CLUSTERED
(
[ID]
) ON [PRIMARY]
GO

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[AB]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[AB]
GO

CREATE TABLE [dbo].[AB] (
[ID] [int] IDENTITY (1, 1) NOT NULL PRIMARY KEY CLUSTERED ,
[Name] [nvarchar] (50) NULL ,
[DOB] [datetime] NULL ,
[Score] [int] NULL
) ON [PRIMARY]
GO

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[AC]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[AC]
GO

CREATE TABLE [dbo].[AC] (
[ID] [int] IDENTITY (1, 1) NOT NULL ,
[Name] [nvarchar] (50) NULL ,
[DOB] [datetime] NULL ,
[Score] [int] NULL ,
CONSTRAINT ID_PK PRIMARY KEY (ID)
) ON [PRIMARY]
GO

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PRIMARY KEY

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