View the redo log switching frequency of Oracle

View the redo log switching frequency of Oracle

The two SQL statements have the same principle, and the second uses the statistical function.
 
Time unit: minute

Method 1,
Select * from v $ log a where a. THREAD # = 1;
 
Set line 200
Select B. SEQUENCE #, B. FIRST_TIME,. SEQUENCE #,. FIRST_TIME, round (. FIRST_TIME-b.FIRST_TIME) * 24) * 60, 2) from v $ log_history a, v $ log_history B where. SEQUENCE # = B. SEQUENCE # + 1 and B. THREAD # = 1 order by. SEQUENCE # desc;

Method 2,
Set line 200
Select sequence #, first_time, nexttime, round (first_time-nexttime) * 24) * 60, 2) diff from (select sequence #, first_time, lag (first_time) over (order by sequence #) nexttime from v $ log_history where thread # = 1) order by sequence # desc;