多选题In which three cases does a checkpoint occur？ （）AEvery three minutes.BWhen a log switch occurs.CWhen forces by an administrator.DWhen a tablespace is taken offline normal.EWhen the redo buffer is one-third full.
题目
多选题
In which three cases does a checkpoint occur？ （）
A
Every three minutes.
B
When a log switch occurs.
C
When forces by an administrator.
D
When a tablespace is taken offline normal.
E
When the redo buffer is one-third full.