Question

我是LINQ的新手，我有查询，我用SQL服务器编写，我想翻译/转换为LINQ.Can任何人都指导我正确的方向？ THX

这是我的SQL：

SELECT Contact.Name, Contact.E-Mail, 
       Contact Business Relation.No_
FROM   Contact Business Relation RIGHT OUTER JOIN
          Contact ON Contact Business Relation.Contact No_ = Contact.Company No_
WHERE  (Contact.E-Mail = @mail)

这是我的LINQ（我不确定我做得对吗）：

                var query = from cbr in db.Contact_Business_Relation
                           join c in db.Contact
                           on cbr.Contact_No_ equals c.Company_No_ into f
                           from c in f.DefaultIfEmpty()
                           where c.E_Mail == Mail
                           select new
                           {
                               Mail = c.E_Mail,
                               No = cbr.No_
                           };

Answer 1

不幸的是，linq没有正确的联接。但是，您可以重新排列查询以使用左连接。

var query = from c in db.Contact
            join cbr in db.Contact_Business_Relation
            on c.Company_No_ equals cbr.Contact_No_ into f
            from cbr in f.DefaultIfEmpty()
            where c.E_Mail == Mail
            select new
            {
              Mail = c.E_Mail,
              No = cbr.No_
            };

Join Clause

linq-to-sql中的右外连接

1 个答案: