to get the most expensive t_SQL

it is easy and popular to know that you can query on DMV to pull out the most expensive queires as below.

 

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

 

While, if your DB is still in the 80 compbility level, you have to resrot to some coding to fecth the SQL text from DMVs.

 

This thread is to log what I did for this purpose this morning.

 

 

--for the the database compatibility level is only at 80.

declare @workTable table

(

id int identity(1,1) primary key,

handler varbinary(64),

statement_start_offset int,

statement_end_offset int,

sqltext nvarchar(4000)

)

declare @handler varbinary(64)

declare @sqlText nvarchar(4000)

declare @statement_start_offset int

declare @statement_end_offset int

declare @i int

declare @rowcnt int

set @i=1

set @rowcnt=200

insert into @workTable

select top (@rowcnt) [sql_handle],statement_start_offset, statement_end_offset, null from sys.dm_exec_query_stats

ORDER BY total_worker_time DESC --Here i get out the expensive CPU time

--order by total_logical_reads desc

-- ORDER BY total_logical_writes DESC -- logical writes

-- ORDER BY total_worker_time DESC -- CPU time

while @i<=@rowcnt

begin

    select @handler =handler, @statement_start_offset=statement_start_offset,

            @statement_end_offset=statement_end_offset

    from @workTable where id=@i

    select @sqltext=SUBSTRING(TEXT,(@statement_start_offset/2)+1,

                                    ((CASE @statement_end_offset when -1 THEN DATALENGTH(TEXT)

                                                                ELSE @statement_end_offset

                                        END - @statement_start_offset)/2)+1)

    from sys.dm_exec_sql_text(@handler)

    update @workTable

    set sqltext=@sqltext where id=@i

    set @i=@i+1

end

select * from @worktable