How to change programmatically non-identity column to identity one?

Question

I have a table with column ID that is identity one. Next I create new non-identity column new_ID and update it with values from ID column + 1. Like this:

new_ID         


        

Answer 1

Looks like SQL Mobile supports altering a columns identity but on SQL Server 2005 didn't like the example from BOL.

So your options are to create a new temporary table with the identity column, then turn Identity Insert on:

Create Table Tmp_MyTable ( Id int identity....)

SET IDENTITY_INSERT dbo.Tmp_Category ON

INSERT Into Tmp_MyTable (...)
Select From MyTable ....

Drop Table myTable

EXECUTE sp_rename N'dbo.Tmp_MyTable', N'MyTable', 'OBJECT' 

Additionally you can try and add the column as an identity column in the first place and then turn identity insert on. Then drop the original column. But I am not sure if this will work.