Question

目前，我们正在使用数据表过滤和排序数据。

    /// <summary>
    /// Filters the data table and returns a new data table with only the filtered rows.
    /// </summary>
    /// <param name="dtInput">The dt input.</param>
    /// <param name="filterExpression">The filter expression.</param>
    /// <returns></returns>
    protected virtual DataTable FilterDataTable(DataTable dtInput, string filterExpression)
    {
            DataTable t1 = dtInput.Clone();
            if(!string.IsNullOrEmpty(filterExpression) && filterExpression.Trim().Length > 0)
            {
                t1.BeginLoadData();
                foreach (DataRow r in dtInput.Select(filterExpression))
                {
                    t1.Rows.Add(r.ItemArray);
                }
                t1.EndLoadData();
            }
            else
            {
                t1 = dtInput;
            }

        return t1;
    }

是否有其他Collection / Container经过优化以进行此类过滤/排序？我们正在查看SortedList或Dictionary。目前，对DataTable进行排序和过滤需要15到25秒。

数据样本

HierarchyNodeId ParentHierarchyNodeId NodeName  ExternalIdentifier
    71  57  Skin Care Preparations - 3400   3400
    72  56  UNKNOWN - 1110  1110
    73  57  Sanitary Protection - 3380  3380
    74  57  Kitchen Gadgets - 2890  2890
    75  45  Seasonal GM - 2970  2970
    76  52  UNKNOWN - 2500  2500
    77  45  Juices & Drinks-Refrig - 2100   2100
    78  56  Housewares, Appliances - 2870   2870
    79  45  Condiments/Gravies/Sauce - 1170 1170
    80  63  UNKNOWN - 2325  2325

过滤示例

HierarchyNodeId in (288,217,503,426,497,211,317,603,612,549,311,526,125,449,520,3071,2919,2624,85,111,3025,297,397,2833,2653,532,194,171,480,380,403,3105,271,457,134,205,632,420,2959,446,105,626,2641,2988,234,334,357,148,572,463,71,509,165,489,303,277,377,483,248,589,197,185,291,583,191,2707,477,500,340,240,552,546,623,2567,523,2773,363,2696,469,177,228,2982,2796,2690,506,320,220,606,114,609,323,2813,394,108,91,383,406,2713,615,268,563,168,560,300,88,2787,374,274,423,82,400,294,188,580,529,137,2942,2601,146,169,432,455,2902,540,440,122,360,145,74,3062,569,2661,460,2685,355,2971,564,2579,461,561,538,3079,351,592,2899,94,586,486,2825,352,275,326,140,246,123,624,547,223,2877,2668,409,2771,117,2897,2659,429,172,381,452,567,272,2582,558,458,166,3003,2791,249,3077,349,484,226,232,252,152,2951,332,354,174,466,2956,280,378,143,243,535,2858,156,182,251,543,331,386,437,3040,100,2646,628,371,159,76,3093,262,368,474,3090,2961,3067,365,471,577,153,130,259,236,2964,574,362,339,127,233,445,342,551,256,2784,77,2616,595,524,601,209,315,309,415,395,545,439,79,2569,548,2781,2910,2672,2993,336,442,438,338,2636,335,97,2851,358,3060,149,126,621,306,2665,183,418,2908,203,389,495,283,464,120,2822,412,2719,229,515,441,255,289,312,527,3014,2805,598,521,103,498,318,212,604,2887,413,625,2820,3034,200,329,541,435,3050,348,454,608,242,139,3114,3120,206,492,421,180,106,129,235,245,2543,2735,2732,136,3032,201,522,307,95,519,416,92,198,304,410,516,3006,133,110,322,216,428,534,345,557,451,239,2835,319,425,301,407,387,493,281,175,622,2643,513,3112,2723,596,490,278,593,2743,2849,384,487,2746,333,227,627,392,286,2699,2681,213,554,531,107,316,210,422,448,2764,222,93,585,2818,2924,328,199,116,225,113,219,2815,631,502,162,525,419,2864,2655,2588,121,98,204,101,2717,230,124,590,2932,537,325,408,87,196,620,514,90,431,302,2638,634,528,2867,142,2986,284,178,617,3001,402,299,511,190,273,614,193,508,296,393,287,181,3095,75,499,605,2880,3118,496,155,602,473,261,405,482,588,2632,505,485,119,379,2847,599,258,2620,364,470,367,2915,361,467,573,576,104,444,2912,78,290,2694,184,313,293,81,187,2591,570,207,128,260,517,414,314,2862,157,417,443,208,131,2936,231,343,629,237,337,2650,478,501,611,399,582,267,370,158,138,479,2860,2754,161,476,264,373,135,244,347,453,132,241,450,344,556,2683,3046,238,553,447,2892,530,550,2571,167,424,84,633,376,164,2889,3098,270,472,555,401,163,269,2917,263,610,607,346,109,160,3074,369,83,375,2808,2702,481,89,581,587,189,2991,504,2711,80,366,2628,266,2885,372,86,398,298,3103,186,292,192,584,285,2692,305,2904,308,202,73,391,179,96,2586,565,411,388,176,279,600,173,2875,494,282,385,276,170,2978,150,253,465,594,491,382,359,488,571,597,2801,99,356,568,2612,462,2560,562,118,221,433,350,436,542,330,3052,224,115,456,327,539,324,112,536,2769,2663,195,218,430,321,510,404,2766,427,2869,147,2657,2554,507,533,616,141,2843,144,247,2634,613,250,3055,2740,353)AND ParentHierarchyNodeId in(44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70)`

我知道在数据库中这会快得多。目前，这不是一个选择。我们正在考虑将其移植到数据库中，但是努力和时间表并没有实现。这是未来的计划。

Answer 1

如果在SET中使用HashSet并测试是否在集合中找到HierarchyModelId，该怎么办？

Answer 2

LINQ是您的选择吗？（.NET 3.5）

我认为您可以使用LINQ查询来完成此操作。问题是LINQ不直接支持IN子句。 LINQ使用Contains，它类似于向后的IN子句。

这是一个解释包含的链接以及如何使用“IN” http://blog.ninethsense.com/sql-in-clause-in-linq/

这是一个链接，详细介绍了如何将LINQ与数据表一起使用。 http://dotnetarchitect.wordpress.com/2009/03/18/using-linq-to-manipulate-data-in-datasetdatatable/

用C＃过滤的最快数据结构

2 个答案: