linq表连接

SELECT
    ( SELECT d.DeptName FROM Dept d WHERE d.Id=p.DeptId  ) DeptName,
    count( p.DeptId) AS Count
FROM
   Person p

GROUP BY
    p.DeptId

var dept = (from p in db.Person
                       
                        group p by p.DeptId into g
                        join d in db.Dept
                       on g.Key equals d.Id
                        select new
                        {
                            count=g.Count(),
                            g.Key,
                            DeptName = d.DeptName
                        }
                        
                        ).ToList();


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