【单项选择题】
James Watt()the steam engine.
A、 A.was inventing
B、B.invented
C、C.had invented
D、D.has invented
A、 A.was inventing
B、B.invented
C、C.had invented
D、D.has invented
A、Flashback logging is not enabled for the database. B、The changes made to the table are not committed. C、Supplemental logging is not enabled for the database. D、The database is not configured in ARCHIVELOG mode.