发现EntityFranework的一个问题，这是怎么回事？

2015-04-22 07:26:59 140 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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用两种方式调用同样的Linq查询，
这是第一种：



var LunBoList = from x in nc.Articles

                            where x.PlateId == 4 && x.isShow == true

                            orderby x.ArticleID descending

                            orderby x.isTop descending

                            select new ArticleListModel

                            {

                                ArticleID = x.ArticleID,

                                ShortTitle = x.ShortTitle,

                                Abstract = x.Abstract,

                                ImagesUrl = x.ImagesUrl,

                                NavigateUrl = x.NavigateUrl

                            };

            ViewBag.LunBoList = LunBoList.Take(4).ToList();

这是第二种,调用其它方法查询



ViewBag.TJList = GetArticleListModel(11, 2);



private List<ArticleListModel> GetArticleListModel(int plateId, int top)

{

    NewsContext nc = new NewsContext();

    var LunBoList = from x in nc.Articles

                    where x.PlateId == plateId && x.isShow == true

                    orderby x.ArticleID descending

                    orderby x.isTop descending

                    select new ArticleListModel

                    {

                        ArticleID = x.ArticleID,

                        ShortTitle = x.ShortTitle,

                        Abstract = x.Abstract,

                        ImagesUrl = x.ImagesUrl,

                        NavigateUrl = x.NavigateUrl

                    };

    return LunBoList.Take(top).ToList();

}

生成的数据库语句第一种是这样的



SELECT TOP (4) 

[Extent1].[ArticleID] AS [ArticleID], 

[Extent1].[ShortTitle] AS [ShortTitle], 

[Extent1].[Abstract] AS [Abstract], 

[Extent1].[ImagesUrl] AS [ImagesUrl], 

[Extent1].[NavigateUrl] AS [NavigateUrl]

FROM [dbo].[Articles] AS [Extent1]

WHERE (4 = [Extent1].[PlateId]) AND (1 = [Extent1].[isShow])

ORDER BY [Extent1].[isTop] DESC

第二种是这样的



exec sp_executesql N'SELECT TOP (2) 

[Project1].[ArticleID] AS [ArticleID], 

[Project1].[ShortTitle] AS [ShortTitle], 

[Project1].[Abstract] AS [Abstract], 

[Project1].[ImagesUrl] AS [ImagesUrl], 

[Project1].[NavigateUrl] AS [NavigateUrl]

FROM ( SELECT 

	[Extent1].[ArticleID] AS [ArticleID], 

	[Extent1].[ShortTitle] AS [ShortTitle], 

	[Extent1].[Abstract] AS [Abstract], 

	[Extent1].[ImagesUrl] AS [ImagesUrl], 

	[Extent1].[NavigateUrl] AS [NavigateUrl], 

	[Extent1].[isTop] AS [isTop]

	FROM [dbo].[Articles] AS [Extent1]

	WHERE ([Extent1].[PlateId] = @p__linq__0) AND (1 = [Extent1].[isShow])

)  AS [Project1]

ORDER BY [Project1].[isTop] DESC',N'@p__linq__0 int',@p__linq__0=11