Question : SQL 2005 Update Query??

Trying to update some data in a table named 'Servmed'.  See below for a sample of what I want to update (field names are underlined):


Level1    Servcode        activerate     billtype
1                B                        1.0000        S
6            BO             2.0000              S
6            BO             1.6700              C
27            BO             2.0000              S
27            BO             1.6700              C
29            BO             2.0000              S
29            BO             1.6700              C


'Level1' identifies a customer - most customers have two rows for servcode='BO', for these rows, I want to update the activerate in the row with a 'S' for billtype to match the activerate in the row with 'C' for billtype.  The rates vary from customer to customer, so I can't just update all with the same.  Some customers only have one billtype, so just one row is returned... they can be excluded.

Any suggestions?

Answer : SQL 2005 Update Query??

update Servmed
set activerate = (select activerate
                  from Servmed B
                  where B.Level1 = Servmed.Level1
                  and B.Servcode = Servmed.Servcode
                  and B.billtype = 'C')
where Servmed.Servcode = 'BO' and Servmed.billtype = 'S'