如何重新编号 T-SQL 的系统自增标识列？

Question

I have an auto-increment primary key in a SQL table lets say table look like this:

CREATE TABLE [Table] (--Identifier contains a space and uses a reserved keyword.
    [ID] [int] IDENTITY(1,1) NOT NULL ,
    [Name] [varchar](50) NULL, 
    CONSTRAINT [PK__Table] PRIMARY KEY CLUSTERED ([ID] ASC)
);

ID  |  Name|
1     John
2     Jack
3     Bill 
4     Joe

Then I delete row 2 Jack:

ID  |  Name|
1     John
3     Bill 
4     Joe

And what I want to achieve is to change id column so the table will look like this

ID  |  Name|
1     John
2     Bill 
3     Joe

Is there a way to do it?

Answer 1

I will never do that but you can:

1. create a new autoincrement primary key named ID2
2. delete ID column
3. rename ID2 column as ID

Answer 2

Quick and dirty way to do it is, (my way) -->

select * into yournewtable from youroldtable order by yourIdentityColumn;

Then, open up yournewtable's design, make sure yourIdentityColumn is Identity(1,1).

Then, drop youroldtable.

Then, rename yournewtable to youroldtable! ta-da!

Answer 3

Set identity_insert Table off;
Update Table set ID = 3 where ID = 4;
...
Set identity_insert Table on;

Where Table name is Table