Security
Anything that runs on our database server can cause havoc to our databases. No matter what happens, we want to be sure that our databases cannot be harmed. As we have no control over the contents of scripts that can be called from the database, it seems logical not to have these scripts run by the same operating system user who also owns the Oracle database files and processes. This is why, by default, Oracle chose the user nobody as the default user to run the classical local external jobs. This can be adjusted by editing the contents of $ORACLE_HOME/rdbms/admin/externaljob.ora.
On systems where more databases are using the same $ORACLE_HOME directory, this automatically means that all the databases run their external jobs using the same operating system account. This is not very flexible. Luckily for us, Oracle has changed this in the 11g release where remote external jobs are introduced. In this release, Oracle decoupled the job runner process and the database processes. The job...
