Question

I have a Linq query that returns three data elements.

var billingDateResults = from s in Subscriptions
            .Where(s => (s.ProductCode.Contains("myCode")))
      select { g.ID, BillingDate =s.BILL_THRU, s.ProductCode};

I would like to do distinct type of query on this to limit the results to one record per ID.

var billingDateResults = from s in Subscriptions
            .Where(s => (s.ProductCode.Contains("myCode")))
group s by s.ID into g
select g.FirstOrDefault();

This works but now returns all of the fields in the records and I would like to minimize the amount of data by limiting the results to only the 3 fields in the first example.

What is a good way to do this?

TIA

Answer 1

Group by those three fields then.

var billingDateResults =
    from s in Subscriptions
    where s.ProductCode.Contains("myCode")
    group new
    {
        g.ID,
        BillingDate = s.BILL_THRU,
        s.ProductCode
    } by s.ID into g
    select g.First(); // FirstOrDefault is not necessary, the groups will be non-empty