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如何将以下 LINQ 查询更改为普通 sql 查询

[英]How can i change the following LINQ query as normal sql query

我有一个查询,我需要将其作为普通的 sql 查询,任何人都可以帮助我。 还有没有使用NorthWindDatacontext的任何替代方法,如代码中提到的我的代码如下

private void FetchData(int take, int pageSize)
{           
  using (NorthwindDataContext dc = new NorthwindDataContext())
  {
    var query = from p in dc.Customers
         .OrderBy(o => o.ContactName)
          .Take(take)
            .Skip(pageSize)
        select new
                        {
                          ID = p.CustomerID,
                            Name = p.ContactName,
                            Count = dc.Customers.Count()
                        };

            PagedDataSource page = new PagedDataSource();
            page.AllowCustomPaging = true;
            page.AllowPaging = true;
            page.DataSource = query;
            page.PageSize = 10;
            Repeater1.DataSource = page;
            Repeater1.DataBind();

            if (!IsPostBack)
            {
                RowCount = query.First().Count;
                CreatePagingControl();
            }
        }
    }

我按照Jon的说法尝试过,但我无法得到想要的结果,谁能帮助我

(SELECT [t1].[CustomerID] AS [ID], [t1].[ContactName] AS [Name], (
    SELECT COUNT(*)
    FROM [dbo].[Customers] AS [t2]
    ) AS [Count]
FROM (
    SELECT TOP (10) [t0].[CustomerID], [t0].[ContactName]
    FROM [dbo].[Customers] AS [t0]
    ORDER BY [t0].[ContactName]
    ) AS [t1]
ORDER BY [t1].[ContactName]

在我看来,最简单的方法是查看 LINQ 到 SQL 在做什么。

使用DataContext.Log将查询信息写到某种类型的日志中(例如,写到StringWriter中,您可以在之后打印出其内容)。 它并不总是最干净的 SQL,但它是 IMO 的一个很好的起点。

我意识到这并不能回答您特定查询的问题,但它试图教您钓鱼而不是给您一条鱼,因为它是:)

编辑:按照 RoccoC5 在评论中的建议使用LINQPad是查看为 LINQ 查询生成的 SQL 的另一种好方法。

这是每个 LINQPad 由 LINQ 查询生成的 SQL,其中@p0是要跳过的行数:

SELECT [t3].[CustomerID] AS [ID], [t3].[ContactName] AS [Name], (
    SELECT COUNT(*)
    FROM [Customers] AS [t4]
    ) AS [Count]
FROM (
    SELECT [t2].[CustomerID], [t2].[ContactName], [t2].[ROW_NUMBER]
    FROM (
        SELECT ROW_NUMBER() OVER (ORDER BY [t1].[ContactName]) AS [ROW_NUMBER], [t1].[CustomerID], [t1].[ContactName]
        FROM (
            SELECT TOP (10) [t0].[CustomerID], [t0].[ContactName]
            FROM [Customers] AS [t0]
            ORDER BY [t0].[ContactName]
            ) AS [t1]
        ) AS [t2]
    WHERE [t2].[ROW_NUMBER] > @p0
    ) AS [t3]
ORDER BY [t3].[ROW_NUMBER]

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