Global temporary tables (GTTs) in Oracle have unique properties related to session-based visibility and data persistence:
* B. A TRUNCATE command issued in a session causes all rows in a GLOBAL TEMPORARY TABLE for the issuing session to be deleted: True, TRUNCATE is session-specific for GTTs and will remove all rows inserted by the session that issues the TRUNCATE command.
* D. A GLOBAL TEMPORARY TABLE's definition is available to multiple sessions: The structure of a GTT is persistent and shared across sessions, but the data within is session-specific.
* E. Any GLOBAL TEMPORARY TABLE rows existing at session termination will be deleted: The data in GTTs is private for the session, and when the session ends, the data is deleted automatically.
References:
* Oracle Database Concepts and SQL Language Reference 12c, especially the sections on temporary tables.