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  • 【转】如何新建索引:高开销的缺失索引

    转自http://blog.csdn.net/yangzhawen/article/details/7253746

    索引对查询性能影响极大,不要盲目的新建索引!数据库高开销的缺失索引 ,根据对动态性能视图的统计信息,新建需要的索引!

    select c.name as 库名,c.equality_columns,
    c.inequality_columns,c.included_columns,
    c.statement as 表名,
    c.avg_total_user_cost as 减少的平均成本 ,
    c.avg_user_impact as 百分比收益,
    c.last_user_seek as 使用后影响上次结果,
    c.unique_compiles
    from 
    (
    select a.name,b.* from 
    (
    select d.*
            , s.avg_total_user_cost
            , s.avg_user_impact
            , s.last_user_seek
            ,s.unique_compiles
    from sys.dm_db_missing_index_group_stats s
            ,sys.dm_db_missing_index_groups g
            ,sys.dm_db_missing_index_details d
    where s.group_handle = g.index_group_handle
    and d.index_handle = g.index_handle
    --order by s.avg_user_impact desc
    )  b,
    sys.databases a 
    where a.database_id=b.database_id
    )c
    order by 百分比收益 desc,unique_compiles desc
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  • 原文地址:https://www.cnblogs.com/davidhou/p/5268036.html
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