Question

我的数据库中有以下表格：

thread --- thread_replies ---回复 thread --- thread_tags --- tags

thread: id, title, content, created, author_id

thread_tags: id, thread_id, tag_id

tags: id, name

我可以使用以下选项为某个线程选择标签：

   SELECT GROUP_CONCAT(DISTINCT tags.name ORDER BY tags.name DESC SEPARATOR ',') AS tags
    FROM tags INNER JOIN thread_tags ON tag_id = tags.id
    INNER JOIN thread ON thread_id = thread.id
    WHERE thread.id = 20

但是，我想要做的是当我选择所有线程时，我想选择与每个线程关联的所有标签...

我想构建一个多维数组，如下所示：

    Array
(
    [t_id] => 20
    [title] => this is a title
    [content] => This is content
    [username] => username1
    [a_id] => 35
    [tags] => tag1, tag2, tag3
)

我想知道我可以用什么sql语句为每个线程创建它？

因此，如果我选择所有线程及其相关作者，我怎样才能获得与每个线程关联的标签？

目前我用它来获取每个帖子及其作者：

SELECT thread.id AS t_id, thread.title,
                         thread.content, author.username, author.id AS a_id
                         FROM thread INNER JOIN author ON thread.author_id = author.id

Answer 1

我认为这应该有效：

SELECT distinct thread.title, thread.id as t_id, thread.content, author.username, author.id as a_id,
GROUP_CONCAT(DISTINCT tags.name ORDER BY tags.name DESC SEPARATOR ',') AS tags
from thread join thread_tags on thread.id = thread_tags.thread_id
join tags on thread_tags.tag_id = tags.id
inner join author on author.id = thread.author_id
group by thread.title

在php和sql中标记

1 个答案: