This query would sum per company. Is this what you want in your view?
CREEATE VIEW SumsView
AS
SELECT CompanyID
, SUM(Amount) TotalAmount
FROM Table1
GROUP BY CompanyID
In the question you mention that you want the ID
column to be included in the view but how do you relate the ID to the aggregated sum?
The only way I can think of is that you care to duplicate the sums, like this:
CREEATE VIEW SumsView
AS
SELECT T.ID
, T.CompanyID
, A.TotalAmount
FROM Table1 T
INNER JOIN (SELECT CompanyID
, SUM(Amount) TotalAmount
FROM Table1
GROUP BY CompanyID) A
ON T.CompanyID = A.CompanyID