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  • SQL SERVER索引使用实例

    添加索引
    IF EXISTS (SELECT name FROM sysindexes
              WHERE name = 'IX_writtenExam')
       DROP INDEX testtable.IX_writtenExam
    /*--笔试列创建非聚集索引:填充因子为%--*/
    CREATE NONCLUSTERED INDEX IX_writtenExam
         ON testtable(id)
              WITH FILLFACTOR= 30
    GO

    查询测试
    /*-----指定按索引IX_writtenExam 查询----*/
    declare @startTime datetime
    SET @startTime = GETDATE();
    SELECT sum(ID) FROM testtable with (INDEX=IX_writtenExam)
    declare @endtime datetime
    SET @endtime = GETDATE();
    print datediff(ms,@startTime,@endtime)

    SELECT sum(ID) FROM testtable

    添加数据
    SET IDENTITY_INSERT TestTable ON
    declare @i int
    set @i=1
    while @i<=400000
    begin
        insert into TestTable([id], FirstName, LastName, Country,Note) values(@i, 'FirstName_XXX','LastName_XXX','Country_XXX','Note_XXX')
        set @i=@i+1
    end
    SET IDENTITY_INSERT TestTable OFF

    工欲善其事,必先利其器。
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  • 原文地址:https://www.cnblogs.com/zhangzhu/p/2494994.html
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