Well, this is dafuq of day... :w00t:

About HASHBYTES (from http://msdn.microsoft.com/en-us/library/ms174415.aspx):

1. input size is limited to 8000

2. output size depends on used algorithm, for MD5 you can use CAST(HASHBYTES('MD5', (EmployeeName + CityName)) AS BINARY(16))

3. beware addition NULL...

I like "less magic" - you can update table alias:

UPDATE

P

SET

ProductName = N.ProductName,

Price = N.Price

FROM

dbo.Product P

INNER JOIN

dbo.New_Prices N ON P.ID...