How to update Identity Column from ROW_NUMBER in sql server

Question

Hello,

How to update Identity Column from ROW_NUMBER in sql server 2008?

I am using this query for update but it's getting error:-
Cannot update identity column 'SNO'

set IDENTITY_INSERT tableSalesQuotation ON

update tableSalesQuotation

set

SNO=SubQuery.SNO

from

(SELECT Row_Number() OVER (ORDER BY SNO) as SNO

FROM tableSalesQuotation

) SubQuery

set IDENTITY_INSERT tableSalesQuotation OFF

please help me.

Thanks in Advance.

Ankit Agarwal
Software Engineer