从多对多关系中选择对象并收集对象

Question

我有三个表格：Athletes,Teams和Team_Athletes。 Team_Athletes以多对多关系连接另外两个表。我正在做的是查询数据库，以便向运动员和一队队伍返回一个对象。我目前正在做这与以下两个查询：

var query = (from a in db.Athletes 
       join ta in db.Team_Athletes on a.Id equals ta.AthleteId 
       join t in db.Teams on ta.TeamId equals t.Id 
       where t.OrganizationId == organizationId 
       orderby a.LastName, a.FirstName 
       select new 
       { 
        Athlete = a, 
        Team = t 
       }).ToArray(); 

    var result = from i in query 
       group i by i.Athlete into g 
       select new 
       { 
        Athlete = g.First().Athlete, 
        Teams = g.Select(i => i.Team).ToArray() 
       }; 

我想知道如何查询一起如果可能的话结合起来，但我不能拿出任何工作。思考？

Answer 1

你为什么不只是使用：

var query = from a in db.Athletes 
      join ta in db.Team_Athletes on a.Id equals ta.AthleteId 
      join t in db.Teams on ta.TeamId equals t.Id 
      where t.OrganizationId == organizationId 
      orderby a.LastName, a.FirstName 
      group t by a into g 
      select new { Athlete = g.Key, Teams = g }; 

然后，您可以遍历结果，就像这样：

foreach (var entry in query) 
{ 
    Console.WriteLine("Athlete: {0}", entry.Athlete); 
    foreach (Team t in entry.Teams) 
    { 
     Console.WriteLine("Team: {0}", t); 
    } 
}