POW

描述

用于计算 a 的 b 次方。

别名

POWER
FPOW
DPOW

语法

POW(<a>, <b>)

参数

参数	说明
`<a>`	基数
`<b>`	指数

返回值

返回参数 a 的 b 次方。

特殊情况：

当 a 或 b 为 NULL 时，返回 NULL。
当 b = 0 且 a 不为 NULL 时，永远返回 1。

示例

select pow(2, 0);

+-------------------------------------------+
| pow(cast(2 as DOUBLE), cast(0 as DOUBLE)) |
+-------------------------------------------+
|                                         1 |
+-------------------------------------------+

select pow(2, 10);

+--------------------------------------------+
| pow(cast(2 as DOUBLE), cast(10 as DOUBLE)) |
+--------------------------------------------+
|                                       1024 |
+--------------------------------------------+

select pow(1.2, 2);

+---------------------------------------------+
| pow(cast(1.2 as DOUBLE), cast(2 as DOUBLE)) |
+---------------------------------------------+
|                                        1.44 |
+---------------------------------------------+

select pow(1.2, 2.1);

+-----------------------------------------------+
| pow(cast(1.2 as DOUBLE), cast(2.1 as DOUBLE)) |
+-----------------------------------------------+
|                            1.4664951016517147 |
+-----------------------------------------------+

select pow(2, null);

+------------------------------+
| pow(cast(2 as DOUBLE), NULL) |
+------------------------------+
|                         NULL |
+------------------------------+

select pow(null, 2);

+------------------------------+
| pow(NULL, cast(2 as DOUBLE)) |
+------------------------------+
|                         NULL |
+------------------------------+

POSITIVE RADIANS