类别：: 数值函数（三角函数）

ASIN¶

计算其实参的反正弦值（反正弦）；结果是 [-pi/2, pi/2] 区间中的数字。

语法¶

ASIN( <input_expr> )

实参¶

input_expr: The value or expression to operate on. Must be greater than or equal to -1.0 and less than or equal to +1.0. The data type must be FLOAT.

返回¶

This function returns a value of type FLOAT.

返回范围 [-pi/2, pi/2] 内以弧度（而非度数）为单位的反正弦值。

示例¶

SELECT ASIN(0), ASIN(0.5), ASIN(1);

+---------+--------------+-------------+
| ASIN(0) |    ASIN(0.5) |     ASIN(1) |
|---------+--------------+-------------|
|       0 | 0.5235987756 | 1.570796327 |
+---------+--------------+-------------+