需要帮助使用 Group By 子句重构 LINQ 语句吗？

发布于 2024-12-10 06:43:56 字数 662 浏览 1 评论 0原文

需要重构的 Linq-To-SQL 如下所示：

   var query = from p in Cache.Model.Products
               join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
               where sc.NumberOfMixes ==  mixes
               select new { p.ProductID, p.Name };

具有以下一行：

   group by p.ProductID

我知道 group by 省略了对 select 子句的任何需要，因此两者可以一起存在于同一个 LINQ-To-SQL 语句中，所以有人可以帮忙吗请我重构上面的内容？

帮助我删除结果中的任何重复数据。 <-- 这就是这个问题的全部要点。根据产品使用的风味数量，产品会重复多次。因此，在“ShishaCombinations”表中，一个 ProductID 可能会针对其使用的每种口味重复多次。我想对上面的查询返回的结果进行分组，或者对其进行调用，因为我不想将产品“n”次添加到我的 GUI，因为它在我的结果中出现“n”次。希望这能消除对我正在尝试做的事情的任何困惑。

原文

The Linq-To-SQL that needs refactoring is found below:

   var query = from p in Cache.Model.Products
               join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
               where sc.NumberOfMixes ==  mixes
               select new { p.ProductID, p.Name };

with the following one-liner:

   group by p.ProductID

I know that group by omits any need for the select clause so both can live together in the same LINQ-To-SQL statement so can someone help me refactor the above please?

To help me remove any repeating data in my results. <-- This is the entire point in this question. A product is repeated a number of times based on the number of Flavours that are used by the product. So as a result in the 'ShishaCombinations' table one ProductID may be repeated many times one for each flavour that it uses. I would like to group the results returned from the query above or call distinct on it as I don't want add the product 'n' times to my GUI because it appears 'n' number of times in my results. Hopefully that will clear up any confusion of what I am trying to do.

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疑心病 2024-12-17 06:43:57

您可以在 select 子句之后使用 into 关键字。您不能仅仅分组，因为您正在投影匿名类型。

   var query = from p in Cache.Model.Products
               join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
               where sc.NumberOfMixes ==  mixes
               select new { p.ProductID, p.Name } into productInfo
               group productInfo by productInfo.productId;

You can use into keyword after select clause. You cannot just group by because you are projecting an anonymous type.

   var query = from p in Cache.Model.Products
               join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
               where sc.NumberOfMixes ==  mixes
               select new { p.ProductID, p.Name } into productInfo
               group productInfo by productInfo.productId;

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迷雾森÷林ヴ 2024-12-17 06:43:56

下面的代码就是我所需要的：

        var query1 = (from p in Cache.Model.Products
                     join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
                     where sc.NumberOfMixes == mixes
                     select new { p.ProductID, p.Name }).Distinct();

Ufuk，感谢您的回答。我知道我的答案很简单，哈哈:)

The code below is all what I needed:

        var query1 = (from p in Cache.Model.Products
                     join sc in Cache.Model.ShishaCombinations on p.ProductID equals sc.ProductID
                     where sc.NumberOfMixes == mixes
                     select new { p.ProductID, p.Name }).Distinct();

Ufuk, thanks for answering mate. I knew my answer was a simple one lol : )

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