Outer Join in Linq or EF

Question

I have two tables

T1     T2
-------------
id1    id2
-----------
1      3
2      5
3
4

I want to get a outer join so that I get 1,2,3,4,5

I am using following Linq command

   var newList = (from i in T1
                   join d in T2
                   on i.id1 equals d.id2 into output
                   from j in output.DefaultIfEmpty()
                   select new {i.id});

The out put I get i 1,2,3,4 missing 5. How can I get it to give me newList 1,2,3,4,5 Help Please

Possible duplicate of http://stackoverflow.com/questions/5489987/linq-full-outer-join?rq=1 — Robert McKee, May 29 '13 at 05:19
I already looked at it it has 2 columns on each table could not solve — J. Davidson, May 29 '13 at 05:21

Jan P. · Accepted Answer · 2013-05-29T05:33:45.887

2

There is no direct alternative to OUTER JOIN in LINQ. You have to solve it like this:

Within query you wrote only the i's that also exists in T2 because of the on i.id1 equals d.id2.

var result = T1.Select(item => item.id1).Union(T2.Select(item => item.id2));

edited May 29 '13 at 05:33

answered May 29 '13 at 05:27

Jan P.

3,261
19
26

score 0 · Answer 2 · edited May 23 '17 at 12:05

0

You could use Union like:

var result = T1.Union(T2);

You can refer to this C# linq union question

edited May 23 '17 at 12:05

Community

1
1

answered May 29 '13 at 06:13

Dietz

578
5
14

Outer Join in Linq or EF

2 Answers2