如何得到执行最耗时的前N条T-SQL语句

--得到最耗时的前N条T-SQL语句
--适用于SQL SERVER 2005及其以上版本

--给N赋初值为30
declare @n int set @n=30

;with maco as
(
select top (@n)
plan_handle,
sum(total_worker_time) as total_worker_time ,
sum(execution_count) as execution_count ,
count(1) as sql_count
from sys.dm_exec_query_stats group by plan_handle
order by sum(total_worker_time) desc
)
select t.text ,
a.total_worker_time ,
a.execution_count ,
a.sql_count
from maco a
cross apply sys.dm_exec_sql_text(plan_handle) t

获取有关按平均CPU时间排在最前面的查询的信息：

SELECT TOP 5 total_worker_time/execution_count AS [Avg CPU Time],
SUBSTRING(st.text, (qs.statement_start_offset/2)+1,
((CASE qs.statement_end_offset
WHEN -1 THEN DATALENGTH(st.text)
ELSE qs.statement_end_offset
END - qs.statement_start_offset)/2) + 1) AS statement_text
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS st
ORDER BY total_worker_time/execution_count DESC;