SQLServer待优化语句查询

SELECT top 100  
    (total_elapsed_time / execution_count)/1000 N'平均时间ms'  
    ,total_elapsed_time/1000 N'总花费时间ms'  
    ,total_worker_time/1000 N'所用的CPU总时间ms'  
    ,total_physical_reads N'物理读取总次数'  
    ,total_logical_reads/execution_count N'每次逻辑读次数'  
    ,total_logical_reads N'逻辑读取总次数'  
    ,total_logical_writes N'逻辑写入总次数'  
    ,execution_count N'执行次数'  
    ,creation_time N'语句编译时间'  
    ,last_execution_time N'上次执行时间'  
    ,SUBSTRING(  
        st.text,   
        (qs.statement_start_offset/2) + 1,   
        (  
            (CASE statement_end_offset WHEN -1 THEN DATALENGTH(st.text) ELSE qs.statement_end_offset END - qs.statement_start_offset)/2  
        ) + 1  
    ) N'执行语句'  
    ,qp.query_plan  
FROM  sys.dm_exec_query_stats AS qs 
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st 
CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp  
WHERE  
    SUBSTRING(  
        st.text,   
        (qs.statement_start_offset/2) + 1,  
        (  
            (CASE statement_end_offset WHEN -1 THEN DATALENGTH(st.text) ELSE qs.statement_end_offset END - qs.statement_start_offset)/2  
        ) + 1  
    )  like '%ROW_NUMBER%'  
ORDER BY  total_elapsed_time / execution_count DESC;