mysql 向上取整函数ceil() /ceiling()

ceil() /ceiling()使用实例：

<code class="language-sql">mysql> SELECT CEILING(3.46);
+---------------------------------------------------------+
| CEILING(3.46)                                           |
+---------------------------------------------------------+
| 4                                                       |
+---------------------------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT CEIL(-6.43);
+---------------------------------------------------------+
| CEIL(-6.43)                                             |
+---------------------------------------------------------+
| -6                                                      |
+---------------------------------------------------------+
1 row in set (0.00 sec)</code>

注意：该函数是向上取整，返回的是大于x的最小整数值。注意负数值的情况。