php - 按日期和值分组

Question

我在名为 articles 的表中有 4 列:created_at、articles、keyword 和 category

我有这个查询来分析数据:

SELECT DATE(`created_at`) AS date, COUNT(1) AS articles 
FROM articles 
WHERE `keyword`='keyword1' 
GROUP BY DATE(`created_at`)

这会返回一个关键字每天的文章总数。

我想要一个总数，然后将其分解并将文章分类为每个关键字的 cat1、cat2 或 cat3 .所以给出这样的表格:

|date|keyword|articles|cat1|cat2|cat3| 

虽然我似乎无法做到这一点，所以我们将不胜感激!

Answer 1

select 
DATE(`created_at`),
keyword,
count(*) as TotalCount,
SUM (case when Category = Cat1 then 1 else 0 end) as Cat1Count,
SUM (case when Category = Cat2 then 1 else 0 end) as Cat2Count,
SUM (case when Category = Cat3 then 1 else 0 end) as Cat3Count

from articles
group by DATE(`created_at`), keyword
order by DATE(`created_at`), keyword