> For the complete documentation index, see [llms.txt](https://chesterzhang666.gitbook.io/intro-mysql/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chesterzhang666.gitbook.io/intro-mysql/sql-han-shu/math-function-shu-xue-han-shu.md).

# Math Function 数学函数

```sql
# 数学函数

SELECT ABS(-100);

SELECT ROUND(3.1415926);

SELECT FLOOR(1.1);

SELECT CEIL(1.1);

SELECT POWER(2,3);

SELECT LOG(10,100);

SELECT LN(2.71828);

SELECT SQRT(4);

SELECT PI();

SELECT SIN(1); -- 1 弧度

SELECT COS(1); -- 1 弧度

SELECT TAN(1); -- 1 弧度

SELECT COT(1); -- 1 弧度

SELECT RADIANS(30); -- 角度转弧度

SELECT DEGREES(1); -- 弧度转角度

```