SQL SERVER 给一个大表添加自增主建 执行过程解析

/* 为了防止任何可能出现的数据丢失问题，您应该先仔细检查此脚本，然后再在数据库设计器的上下文之外运行此脚本。*/

-- 设置参数
BEGIN TRANSACTION
SET QUOTED_IDENTIFIER ON
SET ARITHABORT ON
SET NUMERIC_ROUNDABORT OFF
SET CONCAT_NULL_YIELDS_NULL ON
SET ANSI_NULLS ON
SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
COMMIT
BEGIN TRANSACTION

-- 新建一张临时表，并设置自增长列
GO
CREATE TABLE dbo.Tmp_EmailUser
(
ID bigint NOT NULL IDENTITY (1, 1),
CreateTime datetime NULL,
ReceTime datetime NULL,
ServerID int NULL,
Email varchar(250) NULL,
Status int NULL,
IsDel int NULL,
MailNum bigint NULL,
Msg ntext NULL
) ON [PRIMARY]
TEXTIMAGE_ON [PRIMARY]
GO

--设置自增加长状态
SET IDENTITY_INSERT dbo.Tmp_EmailUser ON

-- 开始拷贝表数据到临时表
GO
IF EXISTS(SELECT * FROM dbo.EmailUser)
EXEC('INSERT INTO dbo.Tmp_EmailUser (ID, CreateTime, ReceTime, ServerID, Email, Status, IsDel, MailNum, Msg)
SELECT ID, CreateTime, ReceTime, ServerID, Email, Status, IsDel, MailNum, Msg FROM dbo.EmailUser WITH (HOLDLOCK TABLOCKX)')

-- 设置自增长列状态
GO
SET IDENTITY_INSERT dbo.Tmp_EmailUser OFF

-- 删除原来表
GO
DROP TABLE dbo.EmailUser

-- 对临时表进行改名
GO
EXECUTE sp_rename N'dbo.Tmp_EmailUser', N'EmailUser', 'OBJECT'

-- 添加主键
GO
ALTER TABLE dbo.EmailUser ADD CONSTRAINT
PK_EmailUser PRIMARY KEY CLUSTERED
(
ID
) WITH( STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]

GO

-- 添加索引
CREATE NONCLUSTERED INDEX IX_EmailUser ON dbo.EmailUser
(
Email
) WITH( STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
COMMIT