MySQL - 按标准分组AND计数组合在一起的项目数 - 如何？

Question

Is there a way to execute 1 query that would select all items ("SELECT * FROM t-shirts ), group them by certain criterion ("GROUP BY style , color ") but at the same time count the # of UNIQUE 'color' items that were grouped together? I can do that by cycling through each style->color and count the number of items, but I thought that perhaps there's an easier way of doing that.

Thanks.

PS Solved: remove color from GROUP BY, and used "COUNT (distinct color)":

SELECT *, COUNT (distinct color) FROM t-shirts GROUP BY style

Answer 1

SELECT COUNT(`field`), `style` FROM `t-shirts` GROUP BY `style`

field是主键。

Answer 2

尝试SELECT style, COUNT(*) FROM t-shirts GROUP BY style 。

Answer 3

SELECT style, COUNT(*) AS cnt 
FROM `t-shirts` 
GROUP BY style

Answer 4

Count是一个组函数，也可以与select *一起使用：

SELECT *, COUNT(`field`) FROM `t-shirts` GROUP BY `style`