SQL Update to the SUM of its joined values

Question

I\'m trying to update a field in the database to the sum of its joined values:

UPDATE P
SET extrasPrice = SUM(E.price)
FROM dbo.BookingPitchExtras AS E
INNER         


        

Answer 1

Use a sub query similar to the below.

UPDATE P
SET extrasPrice = sub.TotalPrice from
BookingPitches p
inner join 
(Select PitchID, Sum(Price) TotalPrice
    from  dbo.BookingPitchExtras
    Where [Required] = 1
    Group by Pitchid
) as Sub
on p.Id = e.PitchId 
where p.BookingId = 1