High Water Mark　图示

+---- high water mark of newly created table
|
V
+--------------------------------------------------------+
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

      high water mark after inserting 10,000 rows
                                    |
                                    v
+--------------------------------------------------------+
|x |x |x |x |x |x |x |x |x |x |x |x |  |  |  |  |  |  |  |
|x |x |x |x |x |x |x |x |x |x |x |x |  |  |  |  |  |  |  |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+


      high water mark after inserting 10,000 rows
                                    |
                                    v
+--------------------------------------------------------+
|x |x |x |x |x |x |x |  |  |  |  |  |  |  |  |  |  |  |  |
|x |x |x |x |x |x |x |  |  |  |  |  |  |  |  |  |  |  |  |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+