单选题You are attempting to clear an unarchived redo log file. In order to manually enact a log switch, which of the following statements is appropriate?（）A ALTER DATABASE B ALTER SYSTEM C ALTER USER D ALTER REDO LOG
题目
单选题
You are attempting to clear an unarchived redo log file. In order to manually enact a log switch, which of the following statements is appropriate?（）
A
ALTER DATABASE
B
ALTER SYSTEM
C
ALTER USER
D
ALTER REDO LOG