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  • mssql 小技巧

    代码1:查看sql的执行时间

    SET STATISTICS PROFILE ON 
    SET STATISTICS IO ON 
    SET STATISTICS TIME ON 
    
    select * from Meeting;
    
    SET STATISTICS PROFILE OFF 
    SET STATISTICS IO OFF 
    SET STATISTICS TIME OFF
    
    
    declare @d datetime
    set @d=getdate()
    /*你的SQL脚本开始*/
    select * from Meeting;
    /*你的SQL脚本结束*/
    select [语句执行花费时间(毫秒)]=datediff(ms,@d,getdate()) 

    代码2:创建索引

    IF EXISTS (SELECT * FROM SYSINDEXES WHERE NAME='Ix_Meeting_ID')
    BEGIN
        DROP INDEX Meeting.Ix_Meeting_ID
    END
    ELSE
    BEGIN
     CREATE CLUSTERED INDEX Ix_Meeting_ID
     ON Meeting(id)  
     WITH FILLFACTOR = 30 
    END
    
    
    /*
    UNIQUE--建立唯一索引(UNIQUE索引既可以采用聚集索引结构,也可以采用非聚集索引的结构,如果不指明采用的索引结构,则SQL Server系统默认为采用非聚集索引结构)
    CLUSTERED--建立聚集索引
    NONCLUSTERED--建立非聚集索引
    
    CREATE CLUSTERED INDEX Ix_Meeting_ID
     ON Meeting(id)  
     WITH FILLFACTOR = 30 --填充因子为30%
    */
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  • 原文地址:https://www.cnblogs.com/xcj26/p/3173028.html
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