Linq子查询使用lambda的同一表 [英] Linq subquery same table using lambda

问题描述

我一直在尝试使用Linq和lambda表达式来转换SQL中已经存在的查询，但是我缺少了一些东西...

I've been trying for a while to use Linq and lambda expressions to translate a query that already exists in SQL, but there is something I'm missing...

这是SQL查询:

select o.ord_no from orders o  where 1 <= 
(select count(*) from orders where orders.purch_amt < o.purch_amt 
and orders.ord_date = '2012-02-14')

如何使用Linq和lambda表达式执行相同的查询?

How could I do the same query but using Linq and lambda expressions???

推荐答案

尝试一下:

var date = DateTime.ParseExact("20120214", 
                              "yyyyMMdd", 
                               CultureInfo.InvariantCulture);    

var result = dbContext.orders
        .Where(q => dbContext.orders
                     .Where(s => s.purch_amt < q.purch_amt)
                     .Where(s => s.ord_date == date).Count() > 0)
        .ToList()

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