How do I add auto_increment to a column in SQL Server 2008

问题

I am using SQL Server 2008 and a primary key of a database table I am using is not an IDENTITY column (not sure why). I need to change that.

I am in SQL Server Management Studio in design view, under column properties and for some reason I can't change the identity specifications to Yes.

Is there something that I am missing.. I am new to SQL Server - any ideas on what I am missing??

Here is the create table

CREATE TABLE [dbo].[AR_Transactions](
       [Trans_ID] [bigint] NOT NULL,
       [DateTime] [datetime] NOT NULL,
       [Cashier_ID] [nvarchar](50) NULL,
       [CustNum] [nvarchar](12) NOT NULL,
       [Trans_Type] [nvarchar](2) NOT NULL,
       [Prev_Cust_Balance] [money] NULL,
       [Prev_Inv_Balance] [money] NULL,
       [Trans_Amount] [money] NOT NULL,
       [Payment_Method] [nvarchar](4) NULL,
       [Payment_Info] [nvarchar](20) NULL,
       [Description] [nvarchar](38) NULL,
       [Invoice_Number] [bigint] NOT NULL,
       [Store_ID] [nvarchar](10) NOT NULL,
       [Dirty] [bit] NOT NULL,
       [Station_ID] [nvarchar](5) NULL,
       [Payment_Type] [smallint] NULL,

CONSTRAINT [pkAR_Transactions] 
       PRIMARY KEY CLUSTERED([Store_ID] ASC, [Trans_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]

ALTER TABLE [dbo].[AR_Transactions] 
    ADD CONSTRAINT [DF_AR_Transactions_Trans_ID_AR_Transactions] 
    DEFAULT ((0)) FOR [Trans_ID]

ALTER TABLE [dbo].[AR_Transactions] 
    ADD CONSTRAINT [DF_AR_Transactions_Invoice_Number_AR_Transactions] 
    DEFAULT ((0)) FOR [Invoice_Number]

Here is the query that I need to run... its a complete hack to try to auto-increment my inserts myself

BEGIN TRANSACTION 

INSERT INTO 
        [cresql].[dbo].[AR_Transactions](Trans_ID, DateTime , Dirty, Store_ID, Trans_Type,  
            Cashier_ID, CustNum, Trans_Amount, Prev_Cust_Balance) 
        SELECT  
            (SELECT MAX(Trans_ID ) + 1 FROM [cresql].[dbo].[AR_Transactions]), 
            DATEADD(MINUTE, -30, Getdate()), 1, 1001, 'C', 100199, CustNum,
            -Acct_Balance, Acct_Balance 
    FROM  [cresql].[dbo].[Customer] 
        WHERE Acct_Balance <> 0  

UPDATE [cresql].[dbo].[Customer] 
    SET Acct_Balance = 0 
WHERE Acct_Balance <> 0  

COMMIT TRANSACTION

回答1:

To illustrate Martin's point:

And PS: - as Mikael Eriksson rightfully mentions (and documents nicely), this Identity Specification remains grayed out as long as that column you're working on has a default constraint.

回答2:

You need to expand the "Identity Specification" node to change it via the (Is Identity) property.

This will rebuild the table so you might also need to go into Tools -> Options -> Designers -> Prevent saving changes that require table re-creation.

This can be an extremely time consuming operation on large tables as well as entailing a lot of logging and locking. To perform this operation on a large table see my answer here.

回答3:

Remove the default constraint of column Trans_ID first. Then you can set Is Identity to Yes in the designer.

This is properties for column Trans_ID in your table AR_Transactions. (Is Identity) is disabled:

Remove the default constraint and (Is Identity) is no longer disabled:

Set to yes and save. Default Value or Binding is disabled instead:

回答4:

You can't use ALTER TABLE ... ALTER COLUMN to modify a column to have an identity property. You'll need to

drop the primary key constraint and any foreign key constraints referencing the column in question in your table.
add a new column with the identity property. It should have the same type (int, I presume) as the existing column.
update the table to seed the new column with the values of the existing column.
alter the new column to make it non-nullable.
drop the old/existing column.
rename the new column so that its name is the same as that of the old column.
Recreate the primary key and foreign key references you dropped in the 1st step.

Simple! Or something.

回答5:

CREATE TABLE [dbo].[AR_Transactions](
       [Trans_ID] [bigint] IDENTITY(1,1) NOT NULL,
       [DateTime] [datetime] NOT NULL,
       [Cashier_ID] [nvarchar](50) NULL,
       [CustNum] [nvarchar](12) NOT NULL,
       [Trans_Type] [nvarchar](2) NOT NULL,
       [Prev_Cust_Balance] [money] NULL,
       [Prev_Inv_Balance] [money] NULL,
       [Trans_Amount] [money] NOT NULL,
       [Payment_Method] [nvarchar](4) NULL,
       [Payment_Info] [nvarchar](20) NULL,
       [Description] [nvarchar](38) NULL,
       [Invoice_Number] [bigint] NOT NULL,
       [Store_ID] [nvarchar](10) NOT NULL,
       [Dirty] [bit] NOT NULL,
       [Station_ID] [nvarchar](5) NULL,
       [Payment_Type] [smallint] NULL,

CONSTRAINT [pkAR_Transactions] 
       PRIMARY KEY CLUSTERED([Store_ID] ASC, [Trans_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]

ALTER TABLE [dbo].[AR_Transactions] 
    ADD CONSTRAINT [DF_AR_Transactions_Trans_ID_AR_Transactions] 
    DEFAULT ((0)) FOR [Trans_ID]

ALTER TABLE [dbo].[AR_Transactions] 
    ADD CONSTRAINT [DF_AR_Transactions_Invoice_Number_AR_Transactions] 
    DEFAULT ((0)) FOR [Invoice_Number]

来源：https://stackoverflow.com/questions/6113828/how-do-i-add-auto-increment-to-a-column-in-sql-server-2008

标签

sql

sql-server-2008

auto-increment