I'v been back from USA for more than a week so far and everything is on the right track,like time difference,food,culture and environment etc.This trip is really impressive and absolutely unforgettable,and I'll keep it in mind as a great fortune forever.
The American life is amazing at some points.For example,most of them own a big big house,whereas we just own a small small apartment;basically they drive a SUV car but a few of us drive a uncomfortable car;it is leisure time for them to work because they really enjoy it,but we have to take work as a big part of life and should work hard so that you can keep ahead.
There are many important turn points in life for us,I hope this experience can help myself change some thought about life and work.

Due to work and study,sorry for updating my web blog so late!

In these several months there were great changes about me.

First,I quited my job from Aspire for the consideration of working career.

Second,I realized the importantance of English and made great progress on it.

Third,It's my honor of being a member of a great foreign company which is expanding my career greatly.

Finally,After succeeding in applying for passport and US visa,I'm about to go abord,because I'm going to the US for training next week.

At this moment,I want to change the slogan "One world,One Dream" to "One guy,One Dream".Best wish for meself!

1、put the following file(login.sql) into $ORACLE_HOME；
2、set environment virable：SQLPATH=$ORACLE_HOME
3、the content of file(login.sql) as follows：
define _editor=vi
set serveroutput on size 1000000
set trimspool on
set long 5000
set linesize 100
set pagesize 9999
column plan_plus_exp format a80
column global_name new_value gname
set termout off
define gname=idle
column global_name new_value gname
select lower(user) || '@' || substr( global_name, 1,
decode( dot, 0, length(global_name), dot-1) ) global_name
from (select global_name, instr(global_name,'.') dot from global_name );
set sqlprompt '&gname> '
set termout on

RAC：Oracle rac enables multiple independent servers that are linked by an interconnect to share access to database,providing ha,scalability,and redundancy during failure.RAC provide the benefit of the system failure,such as node failures and instance crashes;

DG：dg ensures ha,data protection,and disaster recovery for enterprise data,it provide the benefit of the site failure.

Flashback Database ：it provide fast recovery from logical data corruption and user errors.

RMAN ：it is an utility that simplifies backing up,restoring,and recovering database files.

RPO(Recovery Point Objective) is focus on the loss of data;

RTO(Recovery Time Objective) is focus on the loss of service.

Some solutions for disaster recovery：

1.Disk array copy technology(EMC SRDF,IBM PPRC,HP BusinessCopy,HDS TrueCopy);

2.Storage volume copy technology(Veritas VVR);

3.Datatabase copy technology(DSG RealSync,Quest SharePlex);

4.Application copy technology.

You should pay attention to three key considerations:

TCO(Total Cost of the Ownership)

ROI(Return On Investment)

BCM(Business Continuity Management)

IBM最近提出了一个smarter planet的plan，旨在着手改善世界，使得人类赖以生存的星球更加智能。试想一下，如果我们能够通过改善电网就能节约50％左右的电能，如果我们能够改善交通就能节省途中时间、减少事故等，如果我们能够提升食品质量就能挽救无辜的生命等等。这不是如果，目前人类已经在打造这些如果成为fact。事实上，现在我们可以借助科技的力量来change这个星球。随着IT技术的发展，我们可以利用新的技术和新的理念来智能化这个世界上的任何事和物，使得它们变得更好，更有效，更加服务于我们这个星球。

目前，该smarter planet还没有一个合适的中文名，这里不妨据我的理解将它翻译为“追梦家园”吧。

最近较闲，着手准备一些技能培训，其中涉及到SQL Tuning，如下是我总结出的10条SQL语句优化精髓：

1、使用绑定变量；

2、产生的redo和undo量越少越好；

3、避免排序操作；

4、避免复杂嵌套的语句；

5、使用索引并正确利用上索引；

6、控制好事务的粒度；

7、走最优的执行计划；

8、编写最佳的等价语句；

9、可不可以使用上物化视图特性和分区特性；

10、正确处理锁等待事件；

这里每一条都可展开一个topic来讲解。先分享给大家，有时间再一一详细的阐述！