Nunca está demás en la cartera de la dama, en el bolsillo del varón saber como bajar una base de datos como cuando las cosas andan mal y la última alternativa que queda es dar con el viejo truco de un OFF/ON.
Acá un resumen en inglés:
Oracle has three shutdown modes:
Normal (default) - waits for in-flight work to complete. This could take houes.
Immediate - terminates all sessions and does a rollback on all
uncommitted transactions.
Abort - aborts all sessions, leaving current DML in need of rollback, de-allocates the SGA and terminates the background processes. Note that a shutdown abort is NOT evil or dangerous. The "abort" simply means that Oracle will terminate all active work, which is what most people want during a shutdown!
Vea la historia completa en: http://www.dba-oracle.com/t_oracle_shutdown_immediate_abort.htm
