Log writer Process - Quiz Explanation
The correct answers are indicated below, along with the text that explains the correct answers.
1.
How many log writers may one database instance have?
Please select the best answer.
A.
Two
B.
One
C.
Ten
D.
Three
The correct answer is B.
Each database instance has exactly one Log Writer process associated with it.
2.
From what part of the log buffer does the Log Writer process write?
Please select the best answer.
A.
The tail of the log
B.
The middle of the log
C.
The head of the log
D.
Randomly from anywhere
The correct answer is A.
New redo entries are added to the head of the log. The Log Writer writes from the other end, the tail, so that redo log entries are written in the order in which they are created.
3.
The Log Writer process takes entries from the log buffer and writes them to where
Please select the best answer.
A.
The archive log files
B.
The datafiles
C.
The redo log files
D.
The control files
The correct answer is C.
Redo log entries are always written to the redo log files. The
LGWR
, or Log Writer, process is responsible for doing this.