Linq include (select * from a table)

Question

I want to know a query in linq which is equivalent to below:

select t1.*, (select columname from table2 t2 where id = 2)
from table1 t1

See if this helps https://learn.microsoft.com/en-us/dotnet/csharp/programming-guide/concepts/linq/basic-linq-query-operations — SoConfused, Aug 21 '18 at 14:24
This might be better https://stackoverflow.com/questions/12859536/simple-select-query-in-linq — SoConfused, Aug 21 '18 at 14:27

score 0 · Accepted Answer · answered Aug 21 '18 at 18:48

Following my SQL to LINQ Recipe, but with a slight twist for the sub-query being in the select:

var ans = from t1 in table
          select new {
              t1,
              columnname = (from t2 in table2
                            where id == 2
                            select columnname).FirstOrDefault()
          };

Note this will be sent to SQL as one query. This is one case where putting the sub-query in another variable will cause LINQ to send two SQL queries instead. SQL requires an (implied) First on the sub-query, but you could leave it off if you don't mind columnname being an IEnumerable that potentially has multiple values.

Linq include (select * from a table)

1 Answers1