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我有这个数据库模型：

我的数据模型

我使用这个查询：

public List<Film> ListFilmsSortiesDes7DerniersJoursDVD()
{
    DateTime dateDans7Jours = DateTime.Now.AddDays(7);
    DateTime dateIlYa7Jours = DateTime.Now.AddDays(-7);
    return Query(f => f.Releases.Where(r => r.Langue.langue_code == "FR" && r.TypeRelease.typerelease_code == "DVD").FirstOrDefault().release_date > dateIlYa7Jours
        && f.Releases.Where(r => r.Langue.langue_code == "FR" && r.TypeRelease.typerelease_code == "DVD").FirstOrDefault().release_date < dateDans7Jours && !string.IsNullOrEmpty(f.film_image)).ToList();
}

但是生成的 SQL 性能很差，大约需要 1.3 秒才能返回结果（使用 SQL Server Express 2008 并且我已经在正确的字段上有索引）：

SELECT [Extent1].[film_id]              AS [film_id],
       [Extent1].[film_image]           AS [film_image],
       [Extent1].[film_image_thumb]     AS [film_image_thumb],
       [Extent1].[film_format]          AS [film_format],
       [Extent1].[film_motsclefs]       AS [film_motsclefs],
       [Extent1].[film_nom]             AS [film_nom],
       [Extent1].[film_nomvf]           AS [film_nomvf],
       [Extent1].[film_synopsis]        AS [film_synopsis],
       [Extent1].[film_anneeproduction] AS [film_anneeproduction],
       [Extent1].[film_budget]          AS [film_budget],
       [Extent1].[film_dateajout]       AS [film_dateajout],
       [Extent1].[film_actif]           AS [film_actif],
       [Extent1].[utilisateur_id]       AS [utilisateur_id],
       [Extent1].[film_francais]        AS [film_francais],
       [Extent1].[film_revenue]         AS [film_revenue],
       [Extent1].[filmgroupe_id]        AS [filmgroupe_id]
FROM   [dbo].[Film] AS [Extent1]
       OUTER APPLY (SELECT TOP (1) [Filter1].[release_date] AS [release_date]
                    FROM   (SELECT [Extent2].[film_id]        AS [film_id],
                                   [Extent3].[release_date]   AS [release_date],
                                   [Extent3].[typerelease_id] AS [typerelease_id]
                            FROM   [dbo].[FilmRelease] AS [Extent2]
                                   INNER JOIN [dbo].[Release] AS [Extent3]
                                     ON [Extent3].[release_id] = [Extent2].[release_id]
                                   INNER JOIN [dbo].[Langue] AS [Extent4]
                                     ON [Extent3].[langue_id] = [Extent4].[langue_id]
                            WHERE  N'FR' = [Extent4].[langue_code]) AS [Filter1]
                           INNER JOIN [dbo].[TypeRelease] AS [Extent5]
                             ON [Filter1].[typerelease_id] = [Extent5].[typerelease_id]
                    WHERE  ([Extent1].[film_id] = [Filter1].[film_id])
                           AND (N'CINEMA' = [Extent5].[typerelease_code])) AS [Limit1]
       CROSS APPLY (SELECT TOP (1) [Filter3].[release_date] AS [release_date]
                    FROM   (SELECT [Extent6].[film_id]        AS [film_id],
                                   [Extent7].[release_date]   AS [release_date],
                                   [Extent7].[typerelease_id] AS [typerelease_id]
                            FROM   [dbo].[FilmRelease] AS [Extent6]
                                   INNER JOIN [dbo].[Release] AS [Extent7]
                                     ON [Extent7].[release_id] = [Extent6].[release_id]
                                   INNER JOIN [dbo].[Langue] AS [Extent8]
                                     ON [Extent7].[langue_id] = [Extent8].[langue_id]
                            WHERE  N'FR' = [Extent8].[langue_code]) AS [Filter3]
                           INNER JOIN [dbo].[TypeRelease] AS [Extent9]
                             ON [Filter3].[typerelease_id] = [Extent9].[typerelease_id]
                    WHERE  ([Extent1].[film_id] = [Filter3].[film_id])
                           AND (N'CINEMA' = [Extent9].[typerelease_code])) AS [Limit2]
WHERE  ([Limit1].[release_date] > '2013-02-04T00:07:48' /* @p__linq__0 */)
       AND ([Limit2].[release_date] < '2013-02-18T00:07:48' /* @p__linq__1 */)
       AND ([Extent1].[film_image] IS NOT NULL)

你有什么想法可以提高这个查询的性能吗？

4

1 回答 1

0

好的，当答案很简单时，为什么搜索复杂：

    public List<Film> ListFilmsSortiesDes7DerniersJoursCinema()
    {
        DateTime dateDans7Jours = DateTime.Now.AddDays(7);
        DateTime dateIlYa7Jours = DateTime.Now.AddDays(-7);
        return Query(f => f.Releases.Where(r => r.Langue.langue_code == "FR" && r.TypeRelease.typerelease_code == "CINEMA" && r.release_date > dateIlYa7Jours && r.release_date < dateDans7Jours).Any()).ToList();
    }

我也加入了

于 2013-02-11T12:05:26.783 回答