Count over group

I have a view that I want to count the occurrance of a FedIDNo only once in a
group of linked SSNs (using ROW_NUMBER() OVER ?). For instance, if I have
the following I want to count only 1:

FedIDNo SSN

123456789 987654321
123456789 998877654

Below is my SQL.

SELECT dbo.ClientInfo.FedIDNo, dbo.People.SSN
FROM dbo.Timesheets INNER JOIN
dbo.ClientInfo ON dbo.Timesheets.ClientLinkID =
dbo.ClientInfo.PeopleLinkID INNER JOIN
dbo.People INNER JOIN
dbo.PeopleLink ON dbo.People.PersonID =
dbo.PeopleLink.PersonID ON dbo.Timesheets.WorkerLinkID =
dbo.PeopleLink.PeopleLinkID
GROUP BY dbo.ClientInfo.FedIDNo, dbo.People.SSN


Thanks.

--
David

Assuming you don't want it as part of your result set (which wouldn't
make sense because you have the SSN in there) you just need to use
COUNT(DISTINCT fieldname)...

SELECT COUNT(DISTINCT dbo.ClientInfo.FedIDNo)
FROM dbo.Timesheets INNER JOIN
dbo.ClientInfo ON dbo.Timesheets.ClientLinkID =
dbo.ClientInfo.PeopleLinkID INNER JOIN
dbo.People INNER JOIN
dbo.PeopleLink ON dbo.People.PersonID =
dbo.PeopleLink.PersonID ON dbo.Timesheets.WorkerLinkID =
dbo.PeopleLink.PeopleLinkID


-Eric Isaacs