如何转换SQL查询到LINQ哪个contans子查询

Question

我的查询，如下所示

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

什么是LINQ请帮我等效查询...

Answer 1

试试这个，这是你最好使用join在这种情况下，而不是一个子查询：

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，你可以这样做：

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，它更清楚地显示主查询和子查询。

幸得在Convert SQL Query (with Correlated Subquery) to LINQ in C#