SQL Server, How to set auto increment after creating a table without data loss?

Question

I have a table table1 in SQL server 2008 and it has records in it.

I want the primary key table1_Sno column to be an auto-incrementing col

Answer 1

Below script can be a good solution.Worked in large data as well.

ALTER DATABASE WMlive SET RECOVERY SIMPLE WITH NO_WAIT

ALTER TABLE WMBOMTABLE DROP CONSTRAINT PK_WMBomTable

ALTER TABLE WMBOMTABLE drop column BOMID

ALTER TABLE WMBOMTABLE ADD BomID int IDENTITY(1, 1) NOT NULL;

ALTER TABLE WMBOMTABLE ADD CONSTRAINT PK_WMBomTable PRIMARY KEY CLUSTERED (BomID);

ALTER DATABASE WMlive SET RECOVERY FULL WITH NO_WAIT