关于sql server性能问题排查

 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 qsCROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) stwhere 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;