淺談Oracle優(yōu)化排序的操作
Jun 07, 2016 pm 04:54 PM服務(wù)器首先在sort_area_size指定大小的內(nèi)存區(qū)域里排序,如果所需的空間超過sort_area_size,排序會在臨時表空間里進(jìn)行。在專
Select * from v$sysstat where name like ‘%sort%’;
Sort(disk):要求Io去臨時表空間的排序數(shù)目
Sort(memory):完全在memory中完成的排序數(shù)目
Sort(rows):被排序的行數(shù)合計
Sort(disk)/ Sort(memory)SELECT disk.Value disk,mem.Value mem,(disk.Value/mem.Value)*100 ratio
FROM v$sysstat disk,v$sysstat mem WHERE mem.NAME='sorts (memory)' AND disk.NAME='sorts (disk)';

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