LINQ Using Max() to select a single row

I'm using LINQ on an IQueryable returned from NHibernate and I need to select the row with the maximum value(s) in a couple of fields.

I've simplified the bit that I'm sticking on. I need to select the one row from my table with the maximum value in one field.

var table = new Table { new Row(id: 1, status: 10), new Row(id: 2, status: 20) }

from u in table
group u by 1 into g
where u.Status == g.Max(u => u.Status)
select u

This is incorrect but I can't work out the right form.

BTW, what I'm actually trying to achieve is approximately this:

var clientAddress = this.repository.GetAll()
    .GroupBy(a => a)
    .SelectMany(
            g =>
            g.Where(
                a =>
                a.Reference == clientReference && 
                a.Status == ClientStatus.Live && 
                a.AddressReference == g.Max(x => x.AddressReference) && 
                a.StartDate == g.Max(x => x.StartDate)))
    .SingleOrDefault();

I started with the above lambda but I've been using LINQPad to try and work out the syntax for selecting the Max().

UPDATE

Removing the GroupBy was key.

var all = this.repository.GetAll();

var address = all
            .Where(
                a =>
                a.Reference == clientReference && 
                a.Status == ClientStatus.Live && 
                a.StartDate == all.Max(x => x.StartDate) &&
                a.AddressReference == all.Max(x => x.AddressReference))
            .SingleOrDefault();

I don't see why you are grouping here.

Try this:

var maxValue = table.Max(x => x.Status)
var result = table.First(x => x.Status == maxValue);

An alternate approach that would iterate table only once would be this:

var result = table.OrderByDescending(x => x.Status).First();

This is helpful if table is an IEnumerable<T> that is not present in memory or that is calculated on the fly.

You can also do:

(from u in table
orderby u.Status descending
select u).Take(1);

You can group by status and select a row from the largest group:

table.GroupBy(r => r.Status).OrderByDescending(g => g.Key).First().First();

The first First() gets the first group (the set of rows with the largest status); the second First() gets the first row in that group.
If the status is always unqiue, you can replace the second First() with Single().

LINQ Using Max() to select a single row

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