c# - 如何将 Sql 查询转换为包含子查询的 Linq

Question

我的查询如下

   `Select * from daps_user_activity where Userid In (Select Userid from daps_portaluser  where EMR_ID = 24855) `

linq中的等效查询是什么，请帮助我...

Answer 1

试试这个，最好join在这种情况下使用 a 而不是子查询：

var results = (from a in daps_user_activity
              join u in daps_portaluser on a.Userid equals u.Userid
              where u.EMR_ID == 24855
              select a).ToList()

Answer 2

或者，你可以使用这个：

var results = (from a in daps_user_activity
               from u in daps_portaluser
               where u.EMR_ID == 24855 
               && a.Userid == u.Userid
               select a).ToList()

对我来说，它更清楚地显示了主查询和子查询。

归功于 @Bruno Brant 在Convert SQL Query (with Correlated Subquery) to LINQ in C#