Question

I have 3 columns/fields as part of a generic list: strID, seq, unit
there are a bunch of strIDs that belong to the same unit and they each have a different seq. I’m interested in the row that has the minimum seq per unit(the leader of the group). How would I accomplish this with a LINQ query (a tsql query would also be fine)?

Following is example data:

  strID, seq, unit
    aaa, 3, 1
    bbb, 2, 1
    ccc, 4, 1
    ddd, 8, 2
    eee, 15,2
    fff, 7, 2

My query would get me the following:

leaderID, unit
bbb, 1
fff, 2

Answer 1

Try this on for size:

select x.strID, a.unit
  from (select unit, MIN(seq) as seq from myTable group by unit) a
  join myTable x 
    on a.unit = x.unit and a.seq = x.seq