Setting Up Database Snapshot

I have created a snapshot

CREATE DATABASE AdventureWorks_Snapshot1200 ON
(NAME = N'AdventureWorks_Data', FILENAME=
N'C:Program FilesMicrosoft SQL ServerMSSQL.1MSSQLDataAW_1200.ss')
AS SNAPSHOT Of AdventureWorks


I changed the records
AddressLine1
from 1970 Napa Ct. to 1970 Napa Ct. Apt 1

When i run
select * from Person.Address
AventureWorks_Snapshot1200 where addressid = '1'

select * from Person.Address
AventureWorks where addressid = '1'
Both appear as 1

When i change Apt to 2 and run it both appear 2
Changed again to 3 both appeared as 3 too.


I was under the impression that the snapshot would remain as 1 when the new update 2 has been performed.

Any light be appreciated.