學習blog地址：http://blog.163.com/m13864039250_1/blog/static/213865248201322252255205/

select xidusn,xidslot,xidsqn,object_id,session_id, oracle_username from v$locked_object;
SELECT * FROM ucf_recharge_trade_order o where o.id='201406211326041011010000006415' for update; -- 鎖定 符合條件的一條記錄 直到提交事務 下一個請求才能獲取到這條記錄，並有執行許可權
SELECT * FROM ucf_recharge_trade_order o where o.id='201406211326041011010000006415'  for update wait 1;-- 鎖定 符合條件的一條記錄 等待 1秒，如果1秒沒有鎖定，報異常
SELECT * FROM ucf_recharge_trade_order o where o.id='201406211326041011010000006415'  for update nowait ;--- 鎖定 符合條件的一條記錄 不等待 ，鎖定失敗，立刻報異常
SELECT * FROM ucf_recharge_trade_order o where o.id = 
(select s.order_id from ucf_recharge_trade_suborder s where s.order_id='201406211326041011010000006415') 
for update of o.id;-- 鎖定 符合條件的一條記錄 通常做關聯查詢鎖定某一條記錄 只鎖定 o 表中的一條記錄

SELECT * FROM ucf_recharge_trade_order o where o.id = 
(select s.order_id from ucf_recharge_trade_suborder s where s.order_id='201406211326041011010000006415') 
for update;-- 鎖定兩個表的中滿足條件的行 

select * from ucf_recharge_trade_suborder s where s.order_id='201406211326041011010000006415';
-- SELECT * FROM ucf_recharge_trade_order o  for update;
-- SELECT * FROM ucf_recharge_trade_order o;
select addr,xidusn,xidslot from v$transaction;
select xidusn,xidslot,xidsqn,object_id,session_id, oracle_username from v$locked_object;