时间:2021-07-01 10:21:17 帮助过:19人阅读
list => array(
array(id => 1, title => '这是title'),
array(id => 2, title => '这是title2'),
)//list_id和list里的id关联
tag => array(
array(id => 1, list_id = 1, name => 'tag1'),
array(id => 2, list_id = 1, name => 'tag2'),
array(id => 3, list_id = 2, name => 'tag3'),
);
这样的,该怎样查出
select => array(
array(
id => 1,
title => '这是title',
tag =>array(
array( id =1, name => 'tag1'),
array(id=2,name='tag2')
),
),
array(
id => 2,
title => '这是title2'
tag =>array(
array( id =3, name => 'tag3')
),
),
)
这样的数据?
PS:就像本站的列表是怎么显示的标签的?
list和tag都是数据库里的数据,想要用mysql这样的查询语句查询出来,得到下面的查询结果,在不用foreach这样的php循环语句下得到结果
list => array(
array(id => 1, title => '这是title'),
array(id => 2, title => '这是title2'),
)//list_id和list里的id关联
tag => array(
array(id => 1, list_id = 1, name => 'tag1'),
array(id => 2, list_id = 1, name => 'tag2'),
array(id => 3, list_id = 2, name => 'tag3'),
);
这样的,该怎样查出
select => array(
array(
id => 1,
title => '这是title',
tag =>array(
array( id =1, name => 'tag1'),
array(id=2,name='tag2')
),
),
array(
id => 2,
title => '这是title2'
tag =>array(
array( id =3, name => 'tag3')
),
),
)
这样的数据?
PS:就像本站的列表是怎么显示的标签的?
SELECT posts.id AS post_id, posts.title AS post_title, GROUP_CONCAT(tags.name AS tag_name)
FROM posts, tag_posts, tags
WHERE tag_posts.post_id = posts.id
AND tag_posts.tag_id = tags.id
GROUP BY post_title
额,突然明白过来你可能是在问MySQL的查询语句..好囧,好像这个需求能用JOIN
搞定?SELECT * FROM `list` LEFT JOIN `tag` ON list.id = tag.list_id
,这个试试?
$lists = array();
foreach($list as $item)
$lists[ $item['id'] ] = array('id'=>$item['id], 'title'=>$item['title']);
foreach($tag as $item) {
$lists[ $item['list_id'] ]['tag'][] = array('id'=>$item['id'], 'name'=>$item['name']);
/*为了得到你的问题中的效果,其实这步有点多余。*/
$lists = array_values($lists);