Mysql sql按值计数按不同值堆栈
我的数据库如下所示:Mysql sql按值计数按不同值堆栈,mysql,sql,join,Mysql,Sql,Join,我的数据库如下所示: table1(article) id | name | description | cat_id 0 | val1 | desc1 | 1 1 | val2 | desc2 | 2 2 | val3 | desc3 | 1 3 | val4 | desc4 | 2 4 | val5 | desc5 | 1 5 | val6 | desc6 | 2 6 | val7 | des
table1(article)
id | name | description | cat_id
0 | val1 | desc1 | 1
1 | val2 | desc2 | 2
2 | val3 | desc3 | 1
3 | val4 | desc4 | 2
4 | val5 | desc5 | 1
5 | val6 | desc6 | 2
6 | val7 | desc7 | 0
table2(categories)
id | name
0 | shoe
1 | glove
2 | hat
它应返回:
articles_connected | categorie_name
3 | glove
0 | shoe
3 | hat
我试过:
SELECT
COUNT(Category.id) as article_amount, Category.name
FROM
article_table as Article,
category_table as Category
WHERE
Category.id = Article.cat_id
这段代码只是把所有的都算为一,并没有把我的类别分开。我不确定出了什么问题。试试看
SELECT
COUNT(Category.id) as article_amount, Category.name
FROM
article_table as Article,
category_table as Category
WHERE
Category.id = Article.cat_id
group by Category.name
请解释您所需的输出是否应计算每个类别的连接文章?count(category.id==article.cat_id)<如我的返回表所示?但例如,您有许多带有cat
hat
的文章,但在您的输出中它显示0
,事实上hat=3和shoe=0,很抱歉,我忘记了分组方式。!谢谢,我的sql查询很好,它只需要按Category.id分组和按Category.name排序