关于SQLserver的索引的一些脚本

--判断无用的索引：
SELECT TOP 30
        DB_NAME() AS DatabaseName ,
        '[' + SCHEMA_NAME(o.Schema_ID) + ']' + '.' + '['
       + OBJECT_NAME(s.[object_id]) + ']' AS TableName ,
        i.name AS IndexName ,
        i.type AS IndexType ,
       s.user_updates ,
       s.system_seeks + s.system_scans + s.system_lookups AS [System_usage]
FROM    sys.dm_db_index_usage_stats s
        INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id]
                                    AND s.index_id = i.index_id
        INNER JOIN sys.objects o ON i.object_id = O.object_id
WHERE   s.database_id = DB_ID()
        AND OBJECTPROPERTY(s.[object_id], 'IsMsShipped') = 0
        AND s.user_seeks = 0
AND s.user_scans = 0
        AND s.user_lookups = 0
        AND i.name IS NOT NULL
ORDER BY s.user_updates DESC ;

---判断哪些索引缺失： 

SELECT TOP 30
       ROUND(s.avg_total_user_cost * s.avg_user_impact * ( s.user_seeks
                                                           + s.user_scans ),
             0) AS [Total Cost] ,
        s.avg_total_user_cost * ( s.avg_user_impact / 100.0 ) * ( s.user_seeks
                                                              + s.user_scans ) AS Improvement_Measure ,
        DB_NAME() AS DatabaseName ,          d.[statement] AS [Table Name] ,
        equality_columns ,
        inequality_columns ,
        included_columns
FROM    sys.dm_db_missing_index_groups g
       INNER JOIN sys.dm_db_missing_index_group_stats s ON s.group_handle = g.index_group_handle
        INNER JOIN sys.dm_db_missing_index_details d ON d.index_handle = g.index_handle
WHERE   s.avg_total_user_cost * ( s.avg_user_impact / 100.0 ) * ( s.user_seeks
                                                              + s.user_scans ) > 10
ORDER BY [Total Cost] DESC ,
        s.avg_total_user_cost * s.avg_user_impact * ( s.user_seeks
                                                      + s.user_scans ) DESC  

---看看那些索引维护成本很高 通俗的说就是更新次数大于使用这个索引的次数
SELECT TOP 20
        DB_NAME() AS DatabaseName ,
        '[' + SCHEMA_NAME(o.Schema_ID) + ']' + '.' + '['
        + OBJECT_NAME(s.[object_id]) + ']' AS TableName ,
        i.name AS IndexName ,
        i.type AS IndexType ,
        ( s.user_updates ) AS update_usage ,
        ( s.user_seeks + s.user_scans + s.user_lookups ) AS retrieval_usage ,
        ( s.user_updates ) - ( s.user_seeks + user_scans + s.user_lookups ) AS maintenance_cost ,
        s.system_seeks + s.system_scans + s.system_lookups AS system_usage ,
        s.last_user_seek ,
        s.last_user_scan ,
        s.last_user_lookup
FROM    sys.dm_db_index_usage_stats s
        INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id]
                                    AND s.index_id = i.index_id
        INNER JOIN sys.objects o ON i.object_id = O.object_id
WHERE   s.database_id = DB_ID('{0}')
        AND i.name IS NOT NULL
        AND OBJECTPROPERTY(s.[object_id], 'IsMsShipped') = 0
   AND ( s.user_seeks + s.user_scans + s.user_lookups ) > 0
ORDER BY maintenance_cost DESC;

----常常使用的索引查看 看看你常用使用的索引是否建立的合理
SELECT TOP 20
DB_NAME() AS DatabaseName
, '['+SCHEMA_NAME(o.Schema_ID)+']'+'.'+'['+OBJECT_NAME(s.[object_id]) +']'AS TableName
, i.name AS IndexName
, i.type as IndexType
, (s.user_seeks + s.user_scans + s.user_lookups) AS Usage
, s.user_updates
FROM sys.dm_db_index_usage_stats s
INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id]
AND s.index_id = i.index_id
INNER JOIN sys.objects o ON i.object_id = O.object_id
WHERE s.database_id = DB_ID()
AND i.name IS NOT NULL
AND OBJECTPROPERTY(s.[object_id], 'IsMsShipped') = 0
ORDER BY Usage DESC