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10g中v$latch的底层表X$KSLLD的全称是X$KSLLD: [K]ernel [S]ervice [L]？ Management [L]atch [D]escriptor对于操作系统来说，可以划分为三种lock，我们称之为OS Lock：1.spinlock。最轻量级的lock，当获取不到时，发生自旋，不用发生上下文切换。2.mutex--互斥量。当获取不

想要进一步了解latch建议去看vage写的一系列本版精华贴。http://www.itpub.net/thread-1605241-1-1.htmlhttp://www.itpub.net/thread-1609235-1-1.htmlhttp://www.itpub.net/thread-1617245-1-1.html

declare  myid number;begin  for i in 1..10000000 loop    select id1 into myid from a2_70m where rowid='AAACYJAAEAAAAAUAAA';  end loop;end;/将这段过程在两个会话同时执行

----对某个SQL进行调优任务DECLARE  my_task_name VARCHAR2(30);  BEGIN  my_task_name := DBMS_SQLTUNE.CREATE_TUNING_TASK(sql_id => '3p5t99gj4c02t');DBMS_SQLTUNE.EXECUTE_TUNING_TASK( task_name => my_task_

-----手动创建SQL PROFILE （HINTS需要自己去找）declaresqltext clob;begin       select sql_fulltext into sqltext  from v$sql where sql_id='373x9rquqh040' and child_number=0 ;    dbms_sqltune.import_sql_pr

SPO coe_xfr_sql_profile.log;SET DEF ON TERM OFF ECHO ON FEED OFF VER OFF HEA ON LIN 2000 PAGES 100 LONG 8000000 LONGC 800000 TRIMS ON TI OFF TIMI OFF SERVEROUT ON SIZE 1000000 NUMF "" SQLP SQL>;SE

var 1 VARCHAR2(32);var 2 VARCHAR2(32);var 3 VARCHAR2(32);var 4 VARCHAR2(32);var 5 VARCHAR2(32);exec :1 :='1220364436';exec :2 :='175'; exec :3 :='1220364436';exec :4 :='18979965876';