ORACLE常用SQL(session&badSql)

查看session:
select sess.sid,
sess.serial#,
lo.oracle_username,
lo.os_user_name,
ao.object_name,
lo.locked_mode
from v$locked_object lo, dba_objects ao, v$session sess
where ao.object_id = lo.object_id
and lo.session_id = sess.sid;
alter system kill session '295,495';

查找bad sql的方法:select * from (select buffer_gets, sql_text from v$sqlarea where buffer_gets >500000 order by buffer_gets desc) where rownum<=10;
执行次数多的SQL：select sql_text,executions from (select sql_text,executions from v$sqlarea order by executions desc) where rownum<10;
读硬盘多的SQL：select sql_text,disk_reads from (select sql_text,disk_reads from v$sqlarea order by disk_reads desc) where rownum<10;
排序多的SQL：select sql_text,sorts from (select sql_text,sorts from v$sqlarea order by sorts desc) where rownum<10;
分析的次数太多，执行的次数太少，要用绑变量的方法来写sql:
set pagesize 600; set linesize 1000; select substr(sql_text,1,80) "sql", count(*), sum(executions) "totexecs" from v$sqlarea where executions < 5 group by substr(sql_text,1,80) having count(*) > 30 order by 2;
游标的观察：set pages 100; select sum(a.value), b.name from v$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$open_cursor group by user_name,sql_text having count(0)>40;
查看当前用户&username执行的SQL：select sql_text from v$sqltext_with_newlines where (hash_value,address) in (select sql_hash_value,sql_address from v$session where username='&username') order by address,piece;