I was trying to convert something like this to VBnet over the wekend but wasn't successful. I thinnk it should work in C#.
DataSet ds = new DataSet();
var combinedData = from t0 in ds.Tables[0].AsEnumerable()
join t1 in ds.Tables[1].AsEnumerable()
on t0.Field<string>("id") equals t1.Field<string>("id")
join t2 in ds.Tables[2].AsEnumerable()
on t0.Field<string>("id") equals t2.Field<string>("id")
into grp1
from tb3 in grp1.DefaultIfEmpty()
select new {
ID = t0.Field<string>("id")
};
jdweng
