查看SQLServer最耗资源时间的SQL语句

sql server中,如果想知道有哪些语句是执行效率不高的,应该如何查看呢?下面就将为您介绍sql server中如何查看执行效率不高的语句,供您参考。

1.找出执行时间最长的10条SQL(适用于SQL SERVER 2005及其以上版本)

Sql代码

SELECT top 10    
    (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    
    ) not like '%fetch%'    
ORDER BY  total_elapsed_time / execution_count DESC;    
  
  
如果想对SQL作筛选,可将  
not like '%fetch%'  换成  like '%user%'就可以找出SQL语句中含有user关键字的SQL

2 找出执行最慢的SQL语句(适用于SQL SERVER 2005及其以上版本)

Sql代码

SELECT  
    (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'  
    ,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'  
    ,creation_time N'语句编译时间'  
    ,last_execution_time N'上次执行时间'  
    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;  

3 找出最耗时的前N条T-SQL语句 (适用于SQL SERVER 2005及其以上版本)

Sql代码

--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    
            
/* 结果格式如下    
text     total_worker_time  execution_count   sql_count    
-------- ------------------ ----------------- ---------    
内容略    
*/  

4 平均耗CPU最多的前个SQL (SQL SERVER 2005或以上版本)

Sql代码

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  

5 平均耗CPU最多的前个SQL (SQL SERVER 2008或以上版本)
Sql代码

SELECT TOP 20  
    total_worker_time/1000 AS [总消耗CPU 时间(ms)],execution_count [运行次数],  
    qs.total_worker_time/qs.execution_count/1000 AS [平均消耗CPU 时间(ms)],  
    last_execution_time AS [最后一次执行时间],min_worker_time /1000 AS [最小执行时间(ms)],  
    max_worker_time /1000 AS [最大执行时间(ms)],  
    SUBSTRING(qt.text,qs.statement_start_offset/2+1,   
        (CASE WHEN qs.statement_end_offset = -1   
        THEN DATALENGTH(qt.text)   
        ELSE qs.statement_end_offset END -qs.statement_start_offset)/2 + 1)   
    AS [使用CPU的语法], qt.text [完整语法],  
    qt.dbid, dbname=db_name(qt.dbid),  
    qt.objectid,object_name(qt.objectid,qt.dbid) ObjectName  
FROM sys.dm_exec_query_stats qs WITH(nolock)  
CROSS apply sys.dm_exec_sql_text(qs.sql_handle) AS qt  
WHERE  execution_count>1  
ORDER BY (qs.total_worker_time/qs.execution_count/1000) DESC  

6 总耗CPU最多的前个SQL (SQL SERVER 2008或以上版本)

Sql代码

SELECT TOP 20  
    total_worker_time/1000 AS [总消耗CPU 时间(ms)],execution_count [运行次数],  
    qs.total_worker_time/qs.execution_count/1000 AS [平均消耗CPU 时间(ms)],  
    last_execution_time AS [最后一次执行时间],max_worker_time /1000 AS [最大执行时间(ms)],  
    SUBSTRING(qt.text,qs.statement_start_offset/2+1,   
        (CASE WHEN qs.statement_end_offset = -1   
        THEN DATALENGTH(qt.text)   
        ELSE qs.statement_end_offset END -qs.statement_start_offset)/2 + 1)   
    AS [使用CPU的语法], qt.text [完整语法],  
    qt.dbid, dbname=db_name(qt.dbid),  
    qt.objectid,object_name(qt.objectid,qt.dbid) ObjectName  
FROM sys.dm_exec_query_stats qs WITH(nolock)  
CROSS apply sys.dm_exec_sql_text(qs.sql_handle) AS qt  
WHERE execution_count>1  
ORDER BY  total_worker_time DESC

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