MySQL数学函数简明总结(2)

时间:2014-09-17 02:56来源:网络整理作者:网络点击: 次

分享到：

复制代码代码如下: mysql select ROUND(-1.14), ROUND(-1.9), ROUND(1.14), ROUND(1.9); +--------------+-------------+-------------+------------+ | ROUND(-1.14) | ROUND(-1.9) | ROUND(1.14) | ROUND

复制代码代码如下:

mysql> select ROUND(-1.14), ROUND(-1.9), ROUND(1.14), ROUND(1.9);
+--------------+-------------+-------------+------------+
| ROUND(-1.14) | ROUND(-1.9) | ROUND(1.14) | ROUND(1.9) |
+--------------+-------------+-------------+------------+
| -1 | -2 | 1 | 2 |
+--------------+-------------+-------------+------------+

mysql> select ROUND(1.38,1), ROUND(1.38,0), ROUND(232.38,-1), ROUND(232.38,-2);
+---------------+---------------+------------------+------------------+
| ROUND(1.38,1) | ROUND(1.38,0) | ROUND(232.38,-1) | ROUND(232.38,-2) |
+---------------+---------------+------------------+------------------+
| 1.4 | 1 | 230 | 200 |
+---------------+---------------+------------------+------------------+

10. TRUNCATE(X,Y): 与ROUND(X,Y)功能类似，但不进行四舍五入，只进行截取。

复制代码代码如下:

mysql> select TRUNCATE(1.33,1), TRUNCATE(1.99,1), TRUNCATE(1.99,0), TRUNCATE(19.99,-1);

+------------------+------------------+------------------+--------------------+

| TRUNCATE(1.33,1) | TRUNCATE(1.99,1) | TRUNCATE(1.99,0) | TRUNCATE(19.99,-1) |

+------------------+------------------+------------------+--------------------+

|              1.3 |              1.9 |                1 |                 10 |

+------------------+------------------+------------------+--------------------+

11. SIGN(X): 返回参数Ｘ的符号，Ｘ的值为负、零或正数时返回结果依次为－１，０或１

复制代码代码如下:

mysql> select SIGN(-21), SIGN(-0),SIGN(0), SIGN(0.0), SIGN(21);

+-----------+----------+---------+-----------+----------+

| SIGN(-21) | SIGN(-0) | SIGN(0) | SIGN(0.0) | SIGN(21) |

+-----------+----------+---------+-----------+----------+

|        -1 |        0 |       0 |         0 |        1 |

+-----------+----------+---------+-----------+----------+

12. POW(X,Y), POWER(X,Y)和EXP(X)