Which of these events does not trigger a checkpoint?
A . A redo log file switch.
B . Issuing the ALTER SYSTEM SWITCH LOGFILE command.
C . When LOG_CHECKPOINT_TIMEOUT is reached.
D. When (LOG_CHECKPOINT_INTERVAL* size of LOG_BUFFER) bytes of data is written to the current redo log file.
E . Issuing the ALTER SYSTEM CHECKPOINT command.
Explanation:
Answer D: A checkpoint is triggered when there is a redo log file switch, when the ALTER SYSTEM CHECKPOINT or ALTER SYSTEM SWITCH LOGFILE command is entered, or when LOG_CHECKPOINT_TIMEOUT is reached. The remaining checkpoint trigger is when the bytes of data written to the current redo log file are equal to the product of LOG_CHECKPOINT_INTERVAL and the OS block size.
No comments:
Post a Comment