cpu utilization

Hi all,

what is the differerence between these two queries,please explain in detail

SELECT TOP(256) SQLProcessUtilization AS [SQL Server Process CPU Utilization], 
               SystemIdle AS [System Idle Process], 
               100 - SystemIdle - SQLProcessUtilization AS [Other Process CPU Utilization], 
               DATEADD(ms, -1 * (@ts_now - [timestamp]), GETDATE()) AS [Event Time] 
FROM ( 
      SELECT record.value('(./Record/@id)[1]', 'int') AS record_id, 
            record.value('(./Record/SchedulerMonitorEvent/SystemHealth/SystemIdle)[1]', 'int') 
            AS [SystemIdle], 
            record.value('(./Record/SchedulerMonitorEvent/SystemHealth/ProcessUtilization)[1]', 
            'int') 
            AS [SQLProcessUtilization], [timestamp] 
      FROM ( 
            SELECT [timestamp], CONVERT(xml, record) AS [record] 
            FROM sys.dm_os_ring_buffers WITH (NOLOCK)
            WHERE ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR' 
            AND record LIKE '%<SystemHealth>%') AS x 
      ) AS y 
ORDER BY record_id DESC OPTION (RECOMPILE);

and

WITH DB_CPU_StatsAS(SELECT DatabaseID,DB_Name(DatabaseID)AS[DatabaseName],SUM(total_worker_time)AS[CPU_Time_Ms],CONVERT([smalldatetime], GETDATE())AS[CPU_Stats_DateTime]FROM sys.dm_exec_query_stats AS qs WITH(NOLOCK)CROSSAPPLY(SELECTCONVERT(INT, value)AS[DatabaseID]FROM sys.dm_exec_plan_attributes(qs.plan_handle)WHERE attribute = N'dbid')AS F_DBGROUPBY DatabaseID)SELECT ROW_NUMBER()OVER(ORDERBY[CPU_Time_Ms]DESC)AS[row_num],DatabaseName,[CPU_Time_Ms],CAST([CPU_Time_Ms]*1.0/ SUM([CPU_Time_Ms])OVER()*100.0AS DECIMAL(5,2))AS[CPUPercent],[CPU_Stats_DateTime]FROM DB_CPU_StatsWHERE DatabaseID >4-- system databasesAND DatabaseID <>32767-- ResourceDBORDERBY row_numOPTION(RECOMPILE);