Handling an Oracle Database needs an experienced professional who is well-versed in the system and other Oracle tools.  Any database needs a Database Administrator to handle it and if the database is large there will be multiple administrators to handle the same.  Some of the key responsibilities of an Oracle Database Administrator are:
Timely upgradation by installing new Oracle server and application tools
Modification of database structure as per the requirement given by developers
Allocating and planning system storage requirements for the database
To create primary storage structures and objects post developers designing the application
Adhering the database with Oracle License Agreement
Contrl and monitor user access to the database
Plan for backup and recovery of the database for untoward incidents
Ability to contact Oracle in case of a