在C#中将具有Group by和Haveing子句的Sql查询转换为Linq To Sql查询 [英] Convert Sql query with Group by and Having clause to Linq To Sql query in C#

问题描述

我需要帮助将以下ql查询转换为Linq转换为Sql查询.

I need help to convert following ql query to Linq to Sql query.

select Name, Address
from Entity
group by Name, Address
having count(distinct LinkedTo) = 1

想法是查找仅具有1个不同的LinkedTo值的所有唯一的名称，地址"对.请记住，表中还有其他列.

Idea is to find all unique Name, Address pairs who only have 1 distinct LinkedTo value. Remember that there are other columns in the table as well.

推荐答案

我会尝试这样的事情:

Entity.GroupBy(e => new { e.Name, e.Address})
      .Where(g => g.Select(e => e.LinkedTo).Distinct().Count() == 1)
      .Select(g => g.Key);

您应该在该行之后放置一个断点，并检查所生成的SQL，以查找真正进入数据库的内容.

You should put a breakpoint after that line and check the SQL that is generated to find what is really going to the database.

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