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Oracle 查询锁之间的依赖关系

发表于：2025-01-29 作者：千家信息网编辑

千家信息网最后更新 2025年01月29日，注释：该SQL可查询多会话,非select的DML操作,同时操作A表引起的锁 ..会话之间的关系~ ....下文有该SQL用到的视图/字段的详细注释.. ....若想显示其他字段可以按照自己需求增加

千家信息网最后更新 2025年01月29日Oracle 查询锁之间的依赖关系注释：该SQL可查询多会话,非select的DML操作,同时操作A表引起的锁 ..会话之间的关系~ ....下文有该SQL用到的视图/字段的详细注释.. ....若想显示其他字段可以按照自己需求增加 ..

SQL: SELECT DISTINCT S.SID , /*会话的唯一标识，通常要对某个会话进行分析前，首先就需要获得该会话的SID。*/ --S.SERIAL# /*会话的序号*/, S.STATE /*WAIT STATE~*/ , S.BLOCKING_SESSION , --SESSION IDENTIFIER OF THE BLOCKING SESSION. THIS COLUMN IS VALID ONLY IF BLOCKING_SESSION_STATUS HAS THE VALUE VALID. S.BLOCKING_SESSION_STATUS STATUS, /*THIS COLUMN PROVIDES DETAILS ON WHETHER THERE IS A BLOCKING SESSION: */ ( CASE WHEN SQL_TEXT IS NULL /*LO.REQUEST = 0 */ THEN '(SID:' || S.SID || ')会话 SQL已跑完' ELSE '(SID:' || S.SID || ')会话正执行SQL：' || SQL_.SQL_TEXT END ) SQL_TEXT /*执行完的SQL'SQL_TEXT标记SQL已跑完，否则标记SQL'*/ , --SQL_.SQL_FULLTEXT SQL全文本, S.USERNAME /*创建该会话的用户名*/ , O.OWNER || '.' || O.OBJECT_NAME 锁的对象, --V$SESSION.ROW_WAIT_OBJ#若操作完的该字段值=-1，所以关联的V$LOCKED_OBJECT取锁表 LO.REQUEST , -- Lock mode in which the process requests the lock 会话申请的锁的模式 S.EVENT , S.MACHINE /*客户端的机器名。*/ , S.LOGON_TIME /*登陆时间*/ , 'ALTER SYSTEM KILL SESSION ''' || S.SID || ',' || S.SERIAL# || ''';' KILL --若存在锁情况,会用到KILL锁释放~ FROM V$SESSION S LEFT JOIN V$SQL SQL_ ON SQL_.SQL_ID = S.SQL_ID JOIN V$LOCKED_OBJECT L ON L.SESSION_ID = S.SID JOIN ALL_OBJECTS O ON L.OBJECT_ID = O.OBJECT_ID JOIN V$LOCK LO ON (LO.BLOCK != 0 OR LO.REQUEST != 0 ) --V$LOCK.block => A value of either 0 or 1, depending on whether or not the lock in question is the blocker --V$LOCK.REQUEST => Lock mode in which the process requests the lock:下文有值的意义~ ['0 - none'] WHERE LO.SID = L.SESSION_ID AND LO.SID = S.SID ORDER BY S.BLOCKING_SESSION DESC ;

注释： --视图==官网注释

--v$session == http://docs.oracle.com/cd/E11882_01/server.112/e40402/dynviews_3016.htm#REFRN30223 --V$SQL == http://docs.oracle.com/cd/E11882_01/server.112/e40402/dynviews_3043.htm#REFRN30246 --V$LOCK == http://docs.oracle.com/cd/E11882_01/server.112/e40402/dynviews_2027.htm#REFRN30121 --V$LOCKED_OBJECT == http://docs.oracle.com/cd/E11882_01/server.112/e40402/dynviews_2030.htm#REFRN30125 --ALL_OBJECTS == http://docs.oracle.com/cd/E11882_01/server.112/e40402/statviews_1158.htm#REFRN20146

--显示字段==官网注释： V$SESSION.STATE = Wait state :

--WAITING - Session is currently waiting --WAITED UNKNOWN TIME - Duration of the last wait is unknown; this is the value when the parameter TIMED_STATISTICS is set to false --WAITED SHORT TIME - Last wait was less than a hundredth of a second --WAITED KNOWN TIME - Duration of the last wait is specified in the WAIT_TIME column S.BLOCKING_SESSION , --Session identifier of the blocking session. This column is valid only if BLOCKING_SESSION_STATUS has the value VALID.

V$SESSION.BLOCKING_SESSION_STATUS = This column provides details on whether there is a blocking session :

--VALID - there is a blocking session, and it is identified in the BLOCKING_INSTANCE and BLOCKING_SESSION columns --NO HOLDER - there is no session blocking this session --NOT IN WAIT - this session is not in a wait --UNKNOWN - the blocking session is unknown