Jun Ding is a Database Specialist, Over 17 years of experience in Oracle Database about Database system architecture,Performance tuning,Trouble shooting,Administrator etc, Support of Oracle 9i/10g/11g/12c/19c in Production.now focuse on database architecture,Performance tuning,such as Oracle,MySQL,etc.He Published many oracle related white papers:such as Oracle Advanced SQL, PL/SQL development and Main author of Oracle technical book: The Art of Oracle Database Development. Co-sponsor of the DBAPLUS, ACOUG, SOUG community(Oracle User Group in China), Participate in online article contribution and offline salon activities of China's famous IT community.His Blog is http://blog.chinaunix.net/uid/7655508.html