Wie überprüfe ich, ob eine gespeicherte Prozedur vorhanden ist?

Alternativen:

USER_PROCEDURES:

SELECT *
  FROM USER_PROCEDURES
 WHERE object_name = 'MY_STORED_PROCEDURE'

USER_OBJECTS:

SELECT *
  FROM USER_OBJECTS
 WHERE object_type = 'PROCEDURE'
   AND object_name = 'MY_STORED_PROCEDURE'