sql server中如何查看执行效率不高的语句

http://database.51cto.com/art/201009/224226.htm

SELECT creation_time  N'语句编译时间'
         ,last_execution_time  N'上次执行时间'
         ,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'
         ,total_worker_time/1000 N'所用的CPU总时间ms'
         ,total_elapsed_time/1000  N'总花费时间ms'
         ,(total_elapsed_time / execution_count)/1000  N'平均时间ms'
         ,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'
 FROM sys.dm_exec_query_stats AS qs
 CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
 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) not like '%fetch%'         
 ORDER BY  total_elapsed_time / execution_count DESC;
 
 select creation_time  N'语句编译时间'
         ,last_execution_time  N'上次执行时间'
         ,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'
         ,total_worker_time/1000 N'所用的CPU总时间ms'
         ,total_elapsed_time/1000  N'总花费时间ms'
         ,(total_elapsed_time / execution_count)/1000  N'平均时间ms'
         ,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' from  sys.dm_exec_query_stats AS qs
  CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
 where st.text like '%from test%'