Tunga frågor efter I/O

SELECT TOP(10) Sum(Q.total_physical_reads) 
               AS 
               [Physical reads], 
               Sum(Q.total_logical_reads) 
               AS [Logical reads], 
               Sum(Q.execution_count) 
               AS [Execution count], 
               Min(COALESCE(Quotename(Db_name(Q.dbid)), N'-') 
                   + N'.' 
                   + COALESCE(Quotename(Object_schema_name(Q.objectid, Q.dbid)), 
                   N'-') 
                   + N'.' 
                   + COALESCE(Quotename(Object_name(Q.objectid, Q.dbid)), N'-')) 
               AS [Module], 
               Min(Q.statement_text) 
               AS [Statement] 
FROM   (SELECT QS.*, 
               ST.dbid                                  AS dbid, 
               ST.objectid                              AS objectid, 
               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) AS statement_text 
        FROM   sys.dm_exec_query_stats AS QS 
               CROSS apply sys.Dm_exec_sql_text(QS.sql_handle) AS ST) AS Q 
--where Q.dbid = db_id() 
GROUP  BY Q.query_hash 
ORDER  BY [logical reads] DESC