Category: SQL

Some times using wrong keys while coding will result in the performance ,to find out such expensive queries in sql

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

You can change the ORDER BY clause to order this table with different parameters. I invite my reader to share their scripts.

Reference: Pinal Dave