如何使转换SQL Inner连接查询与实体框架 [英] How to make conversion SQL Inner joins query vs Entity Framework

问题描述

这里有三个表Service_Orders，Project_Services和Company。服务订单和公司ID之间有3个表之间的内部连接。
我想要下面的查询使用C＃或Vb.net将Lambda Express转换为Entity框架。

Here are three tables Service_Orders, Project_Services and Company. There is inner join between 3 tables by Service Order and CompanyID. I want below query to convert into Entity framework with Lambda Express using C# or Vb.net.

select top 10 * from [Service_Orders] a,[Project_Services] b,[Company] c 
where a.so_no = b.service_order and c.companyId = b.compid

推荐答案

Lambda语法：

var query = db.Service_Orders
              .Join(db.Project_Services,
                    a => a.so_no equals,
                    b => b.service_order,
                    (a,b) => new { a, b })
              .Join(db.Company,
                    x => x.b.compid,
                    c => c.companyId,
                    (x,c) => new { x.a, x.b, c })
              .Take(10);

更多可读查询语法：

var query = (from a in db.Service_Orders
             join b in db.Project_Services on a.so_no equals b.service_order
             join c in db.Company on b.compid equals c.companyId
             select new { a, b, c }).Take(10);

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