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  • oracle SQL语句

    oracle SQL语句执行的监控脚本![@more@]

    --查找bad sql的方法: 
      select * from (select buffer_gets, sql_text 
      from v$sqlarea 
      where buffer_gets >500000 
      order by buffer_gets desc) where rownum<=30;


      --執行次數SQL

      select sql_text,executions from 
      (select sql_text,executions from v$sqlarea order by executions desc) 
      where rownum<81;


      --讀磁盤多的SQL

      select sql_text,disk_reads from 
      (select sql_text,disk_reads from v$sqlarea order by disk_reads desc) 
      where rownum<21;


      --排序多的SQL

      select sql_text,sorts from 
      (select sql_text,sorts from v$sqlarea order by sorts desc) 
      where rownum<21;


      --分析次數太多,執行次數太少,要用綁定綁定變量寫sql

      set pagesize 600; 
      set linesize 120; 
      select substr(sql_text,1,80) "sql", count(*), sum(executions) "totexecs" 
      from v$sqlarea 
      where executions < 5 
      group by substr(sql_text,1,80) 
      having count(*) > 30 
      order by 2;


      --遊標的觀察

      set pages 300; 
      select sum(a.value), b.name 
      from v$sesstat a, v$statname b 
      where a.statistic# = b.statistic# 
      and b.name = 'opened cursors current' 
      group by b.name; 
      select count(0) from v$open_cursor; 
      select user_name,sql_text,count(0) from v$open_cursor 
      group by user_name,sql_text having count(0)>30;


    --查看當前用戶執行的SQL
    select sql_text from v$sqltext_with_newlines where (hash_value,address) in 
      (select sql_hash_value,sql_address from v$session where username='&username') 
      order by address,piece;

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  • 原文地址:https://www.cnblogs.com/Leo_wl/p/4614666.html
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