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计数连接到特定表mysql的记录_Mysql - Fatal编程技术网

计数连接到特定表mysql的记录

计数连接到特定表mysql的记录,mysql,Mysql,我在MYSQL数据库中有两个表,叫做followinews和views。新闻包含关于新闻的信息,而视图基本上包含关于视图和新闻ID的信息。我想要的是检索所有与它连接的视图数的新闻。这是我到目前为止尝试过的,但是它似乎只返回1行 SELECT n.id, n.title, n.image_url, n.date, Count(v.news_id) from news n join views v on v.news_id = n.id aggregate函数withoutgroupby始

我在MYSQL数据库中有两个表,叫做followinews和views。新闻包含关于新闻的信息,而视图基本上包含关于视图和新闻ID的信息。我想要的是检索所有与它连接的视图数的新闻。这是我到目前为止尝试过的,但是它似乎只返回1行

SELECT 
n.id, 
n.title, 
n.image_url, 
n.date,
Count(v.news_id)
from news n
join views v on v.news_id = n.id

aggregate函数
without
groupby
始终返回一行,因此需要添加一个
groupby
子句

SELECT 
n.id, 
n.title, 
n.image_url, 
n.date,
Count(v.news_id)
from news n
join views v on v.news_id = n.id
group by n.id

你忘了分组

SELECT n.id, n.title, n.image_url, n.date,Count(v.news_id)
from news n
join views v on v.news_id = n.id
Group by n.id