To be compatible with my live server I need to upgrade postgresql v8.4 running on a CentOS6.4 server to postgresql v9.2. Is there a step by step procedure on this so that I properly remove 8.4, install 9.2 and have it work with PHP? Will CentOS6.4 support the newer version of postgreslq with yum updates or do I have to upgrade to CentOS7?