The configuration parameter, oracle_home directs Postgres Plus Advanced Server to the correct Oracle Home directory in the file system. This parameter can only be set by a superuser and can be set at any level both on and off-line.; thereby allowing a single EDB server to use multiple Oracle client installs and access both older and newer versions of Oracle at the same time. By implementation, if set, the oracle_home configuration parameter will override the default ORACLE_HOME environment variable.