C# 使用Linq透视多个表

您好，我有以下表格需要旋转以获得所需的结果

tblUsername
userId      username
---------------------
 1          jadam
 2          janeb
 3          peterk
 4          rickd

第二张桌子是

tablcolumns
=============
colId     colname
-----------------
  1        Name
  2        Monday
  3        Tuesday
  4        Wednesday
  5        Thursday
  6        Friday
  7        Saturday
  8        Sunday

第三桌

tblSchedule
==================
id   userId   colId   hrs
--------------------------
1      2       3       4
2      3       7       7.5
3      1       8       2 
I am trying to write Linq statem

我想旋转这些表以获得回复，就像

Name  Monday  Tuesday  Wednesday Thursday Friday Saturday Sunday 
jadam   2
janeb           4
peterk                                            7.5
rickd

---

我尝试使用Linq join，但它不起作用。我认为它需要分组，而且我对它不太熟悉。谢谢

LINQ中没有内置的pivot功能。我想您可以编写一个来动态创建select-但是，它可能不会太有效。无论如何，在这种情况下，由于每周的天数不会改变，您可以这样做：

var query = tblUsername.Select(u => new {
    Name = u.username,
    Monday = u.tblSchedule.Where(sch => sch.colId == 2).Sum(sch => sch.hrs),
    Tuesday = u.tblSchedule.Where(sch => sch.colId == 3).Sum(sch => sch.hrs),
    Wednesday = u.tblSchedule.Where(sch => sch.colId == 4).Sum(sch => sch.hrs),
    Thursday = u.tblSchedule.Where(sch => sch.colId == 5).Sum(sch => sch.hrs),
    Friday = u.tblSchedule.Where(sch => sch.colId == 6).Sum(sch => sch.hrs),
    Saturday = u.tblSchedule.Where(sch => sch.colId == 7).Sum(sch => sch.hrs),
    Sunday = u.tblSchedule.Where(sch => sch.colId == 8).Sum(sch => sch.hrs),
});