sql 在SQL中查找性能降低查询

Posted 2021-05-13

–- find out the most expensive queries on SQL Server Box.  

 SELECT   TOP 10   SUBSTRING   (qt.TEXT, (qs.statement_start_offset   /   2)   +   1,  
 ((   CASE   qs.statement_end_offset  
     WHEN    -   1   THEN   DATALENGTH(qt.TEXT)  
     ELSE   qs.statement_end_offset  
  END   -   qs.statement_start_offset)   /   2)   +   1),  
  qs.execution_count,  
  qs.total_logical_reads, qs.last_logical_reads,  
  qs.total_logical_writes, qs.last_logical_writes,  
  qs.total_worker_time,  
  qs.last_worker_time,  
  qs.total_elapsed_time   /   1000000 total_elapsed_time_in_S,  
  qs.last_elapsed_time   /   1000000 last_elapsed_time_in_S,  
  qs.last_execution_time,  
  qp.query_plan  
 FROM   sys.dm_exec_query_stats qs  
     CROSS   APPLY sys.dm_exec_sql_text(qs.sql_handle) qt  
     CROSS   APPLY sys.dm_exec_query_plan(qs.plan_handle) qp  
 ORDER BY   qs.total_logical_reads   DESC    -- logical reads  
 -- ORDER BY qs.total_logical_writes DESC -- logical writes  
 -- ORDER BY qs.total_worker_time DESC -- CPU time  



 --Original by: Pinal Dave (http://blog.SQLAuthority.com)