performance - Linq to SQL - Find element with lowest field value - Performance

Question

Today I am facing a problem of finding the most efficient query to database using Linq To Sql.

I want to get the element from db.ElementsCollection that has lowest element.SomeNumber value.

I simply managed to do it by following query:

var query = db.ElementsCollection
   .First(o => o.SomeNumber == (db.ElementsCollection.Max(or => or.SomeNumber)));

Is there any more efficient query to accomplish this task?

Answer 1

OrderByDescendingプロパティで使用してSomeNumber、最初のアイテムを取得できます。

var query = db.ElementsCollection
              .OrderByDescending(o => o.SomeNumber)
              .First();

または、morelinqを使用できます。

var query = db.ElementsCollection
              .MaxBy(o => o.SomeNumber);

Answer 2

どのようにそのことについて：

var query = db.ElementsCollection.OrderByDescending(o => o.SomeNumber).First();

または

var query = (from o in db.ElementsCollection
            order by o.SomeNumber descending
            select o).First();

TOP(1)SQLクエリ内に変換する必要があります。

Answer 3

それはあなたが望むものではありませんか：

var maxNumber=db.ElementsCollection.OrderByDescending(o=>o.SomeNumber).First();