SQL Server Converts Column to Identifier Column

Question

I am using SQL Server 2008. One int column that I used as the primary key, but not the identifier column (whose value will be increased by 1 automatically). I want to convert this column to an identifiers column. Any solutions?

thanks in advance George

Answer 1

Unfortunately, you cannot change the field to IDENTITYin an existing table.

You should:

• Create a new table with a field IDENTITY
• Problem SET IDENTITY_INSERT ONfor the new table
• Insert data into a new table
• Problem SET IDENTITY_INSERT OFFfor the new table
• Delete old table
• Rename the new table to the old name.

SSMS , .

:

CREATE TABLE plain (id INT NOT NULL PRIMARY KEY)

INSERT
INTO    plain
VALUES  (1000)

script, SSMS:

SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
COMMIT
BEGIN TRANSACTION
GO
CREATE TABLE dbo.Tmp_plain
    (
    id int NOT NULL IDENTITY (1, 1)
    )  ON [PRIMARY]
GO
ALTER TABLE dbo.Tmp_plain SET (LOCK_ESCALATION = TABLE)
GO
SET IDENTITY_INSERT dbo.Tmp_plain ON
GO
IF EXISTS(SELECT * FROM dbo.plain)
     EXEC('INSERT INTO dbo.Tmp_plain (id)
        SELECT id FROM dbo.plain WITH (HOLDLOCK TABLOCKX)')
GO
SET IDENTITY_INSERT dbo.Tmp_plain OFF
GO
DROP TABLE dbo.plain
GO
EXECUTE sp_rename N'dbo.Tmp_plain', N'plain', 'OBJECT' 
GO
ALTER TABLE dbo.plain ADD CONSTRAINT
    PK__plain__3213E83F1A609306 PRIMARY KEY CLUSTERED 
    (
    id
    ) WITH( STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]

GO
COMMIT

Answer 2

sql-, , , , , , , () Idendity 1.