更新时间:2024-11-11 GMT+08:00
GROUP BY
分析语句语法
完整的分析语句语法如下:
SELECT [DISTINCT] (* | expression) [AS alias] [, ...] [GROUP BY expression [, ...] [HAVING predicates]] [ORDER BY expression [ASC | DESC] [, ...]] [LIMIT size OFFSET offset]
其中,GROUP BY表示按值分组。本章节内容将介绍GROUP BY语法参数说明及示例。
按字段的值分组
SELECT age GROUP BY age
age |
---|
28 |
32 |
36 |
按字段别名分组
SELECT account_number AS num GROUP BY num
num |
---|
1 |
16 |
13 |
18 |
按多个字段分组
SELECT account_number AS num, age GROUP BY num, age
num |
age |
---|---|
1 |
32 |
16 |
36 |
13 |
28 |
18 |
32 |
使用SQL函数
函数相关内容请参见函数。
SELECT LENGTH(lastname) AS len, COUNT(*) AS count GROUP BY LENGTH(lastname)
len |
count |
---|---|
4 |
2 |
5 |
2 |
父主题: 分析语句