1

下面是我正在使用的代码，它从中提取的数据库表中有大约 92000 条记录。它现在拉动的方式是拉动所有 92000 条记录，然后进行过滤。我要做的是过滤从数据库中的初始拉取，以便加载页面不需要大约 40 秒。这是我仍然陌生的东西，所以我不知道如何做到这一点并使其符合我的观点

public ViewResult Makes()
{
    var items = (from item in DBCacheHelper.recallslist
                 orderby item.MFGTXT ascending
                 select item.ToDomainRecall()).GroupBy(item => item.MFGTXT).Select(grp => grp.First());


    return View(items);
}

public static IEnumerable<Recall> recallslist
{
    get
    {
        if (c["GetAllRecalls"] == null)
        {
            c.Insert("GetAllRecalls", GetAllRecalls());
            return (IEnumerable<Recall>)c["GetAllRecalls"];
        }
        else
        {
            return (IEnumerable<Recall>)c["GetAllRecalls"];
        }
    }
}



public static IEnumerable<Recall> GetAllRecalls()
{
    using (DealerContext context = new DealerContext())
    {
        var items = from item in context.recalls.ToList<Recall>()
                     select item.ToDomainRecall();
        return items.ToList<Recall>();
    }
}


SELECT 
[Extent1].[RecallsId] AS [RecallsId], 
[Extent1].[RECORD_ID] AS [RECORD_ID], 
[Extent1].[CAMPNO] AS [CAMPNO], 
[Extent1].[MAKETXT] AS [MAKETXT], 
[Extent1].[MODELTXT] AS [MODELTXT], 
[Extent1].[YEARTXT] AS [YEARTXT], 
[Extent1].[MFGCAMPNO] AS [MFGCAMPNO], 
[Extent1].[COMPNAME] AS [COMPNAME], 
[Extent1].[MFGNAME] AS [MFGNAME], 
[Extent1].[BGMAN] AS [BGMAN], 
[Extent1].[ENDMAN] AS [ENDMAN], 
[Extent1].[RCLTYPECD] AS [RCLTYPECD], 
[Extent1].[POTAFF] AS [POTAFF], 
[Extent1].[ODATE] AS [ODATE], 
[Extent1].[INFLUENCED_BY] AS [INFLUENCED_BY], 
[Extent1].[MFGTXT] AS [MFGTXT], 
[Extent1].[RCDATE] AS [RCDATE], 
[Extent1].[DATEA] AS [DATEA], 
[Extent1].[RPNO] AS [RPNO], 
[Extent1].[FMVSS] AS [FMVSS], 
[Extent1].[DESC_DEFECT] AS [DESC_DEFECT], 
[Extent1].[CONEQUENCE_DEFECT] AS [CONEQUENCE_DEFECT], 
[Extent1].[CORRECTIVE_ACTION] AS [CORRECTIVE_ACTION], 
[Extent1].[NOTES] AS [NOTES], 
[Extent1].[RCL_CMPT_ID] AS [RCL_CMPT_ID]
FROM [dbo].[Recalls] AS [Extent1]

更新：

最终我只想从召回表中提取记录，其中 MFGTXT 等于 AutoMake 表中的 MakeName

public class AutoMake
{
    [Key]
    public int MakeID { get; set; }
    public string MakeName { get; set; }

public AutoMake ToDomainAutoMakes()
{
    return new AutoMake
    {
        MakeID = this.MakeID,
        MakeName = this.MakeName
    };
}

}

public class Recall
{
    [Key]
    public int RecallsId { get; set; }
    public string RECORD_ID { get; set; }
    public string CAMPNO { get; set; }
    public string MAKETXT { get; set; }
    public string MODELTXT { get; set; }
    public string YEARTXT { get; set; }
    public string MFGCAMPNO { get; set; }
    public string COMPNAME { get; set; }
    public string MFGNAME { get; set; }
    public string BGMAN { get; set; }
    public string ENDMAN { get; set; }
    public string RCLTYPECD { get; set; }
    public string POTAFF { get; set; }
    public string ODATE { get; set; }
    public string INFLUENCED_BY { get; set; }
    public string MFGTXT { get; set; }
    public string RCDATE { get; set; }
    public string DATEA { get; set; }
    public string RPNO { get; set; }
    public string FMVSS { get; set; }
    public string DESC_DEFECT { get; set; }
    public string CONEQUENCE_DEFECT { get; set; }
    public string CORRECTIVE_ACTION { get; set; }
    public string NOTES { get; set; }
    public string RCL_CMPT_ID { get; set; }

    public Recall ToDomainRecall()
    {
        return new Recall
        {
            RECORD_ID = this.RECORD_ID,
            CAMPNO = this.CAMPNO,
            MAKETXT = this.MAKETXT,
            MODELTXT = this.MODELTXT,
            YEARTXT = this.YEARTXT,
            MFGCAMPNO = this.MFGCAMPNO,
            COMPNAME = this.COMPNAME,
            MFGNAME = this.MFGNAME,
            BGMAN = this.BGMAN,
            ENDMAN = this.ENDMAN,
            RCLTYPECD = this.RCLTYPECD,
            POTAFF = this.POTAFF,
            ODATE = this.ODATE,
            INFLUENCED_BY = this.INFLUENCED_BY,
            MFGTXT = this.MFGTXT,
            RCDATE = this.RCDATE,
            DATEA = this.DATEA,
            RPNO = this.RPNO,
            FMVSS = this.FMVSS,
            DESC_DEFECT = this.DESC_DEFECT,
            CONEQUENCE_DEFECT = this.CONEQUENCE_DEFECT,
            CORRECTIVE_ACTION = this.CORRECTIVE_ACTION,
            NOTES = this.NOTES,
            RCL_CMPT_ID = this.RCL_CMPT_ID

        };
    }
}
4

2 回答 2

0

看起来您的 DBaccess 是在对DBCacheHelper.recallslist.

您需要编辑从/在此函数中运行的 sql。

正如 Eranga 指出的那样，您没有展示如何将大量记录过滤为较少数量的记录。我假设您一次想要 20 个或 100 个？如果是这样，请在此处查看接受的答案：

实现分页的有效方法

具体来说，这部分展示了如何只检索行 x 到 y（其中 x = @p0 + 1 AND y = @p0 + @p1）：

SELECT [t1].[CodCity], 
    [t1].[CodCountry], 
    [t1].[CodRegion], 
    [t1].[Name],  
    [t1].[Code]
FROM (
    SELECT ROW_NUMBER() OVER (
        ORDER BY [t0].[CodCity], 
        [t0].[CodCountry], 
        [t0].[CodRegion], 
        [t0].[Name],
        [t0].[Code]) AS [ROW_NUMBER], 
        [t0].[CodCity], 
        [t0].[CodCountry], 
        [t0].[CodRegion], 
        [t0].[Name],
        [t0].[Code]
    FROM [dbo].[MtCity] AS [t0]
    ) AS [t1]
WHERE [t1].[ROW_NUMBER] BETWEEN @p0 + 1 AND @p0 + @p1
ORDER BY [t1].[ROW_NUMBER]
于 2012-09-10T16:03:55.573 回答
0

如果要在存储库方法之外添加服务器端过滤，则需要将类型返回为 IQueryable 而不是 IEnumerable，并且不要调用 .ToList、.AsEnumerable 或任何其他会导致调用 .GetEnumerator 的方法。此外，你的演员 `(IEnumerable)c["GetAllRecalls"];' 强制 LINQ to Objects 用于后续请求，而不是保留表达式树并使用实体框架。话虽如此，您可能还需要将您对 ToDomainRecall 方法的调用移至应用附加过滤器之后，因为该过滤器无法转换为您的数据库。以下是您需要进行的一些更改：

public ViewResult Makes()
{
    var items = (from item in DBCacheHelper.recallslist
                 orderby item.MFGTXT ascending
                 select item.ToDomainRecall()).GroupBy(item => item.MFGTXT).Select(grp => grp.First());


    return View(items);
}

public static IQueryable<Recall> recallslist
{
    get
    {  
        if (c["GetAllRecalls"] == null)
        {
            c.Insert("GetAllRecalls", GetAllRecalls(context));
        }
        return c["GetAllRecalls"];

    }
}



public static IQueryable<Recall> GetAllRecalls(DealerContext context)
{
        var items = context.recalls;
        return items;
}
于 2012-09-10T18:22:48.657 回答