Question

我需要从't'（线程）返回包含'menu_item_id'= 1的所有项目。

此外，我需要根据f.tag。

过滤以上所有结果

SELECT t.*, u.username AS owner, uu.username AS replyname, a.location
FROM thread t
INNER JOIN filter_thread as ft ON t.thread_id = ft.thread_id
INNER JOIN filter as f ON f.filter_id = ft.filter_id
INNER JOIN users u ON t.owner_id = u.id 
INNER JOIN users uu ON t.last_post_id = uu.id
INNER JOIN user_profiles AS up ON u.id = up.user_id
INNER JOIN avatars AS a ON up.avatar_id = a.id
WHERE t.menu_item_id='1'
AND f.tag LIKE '%hello%'
OR f.tag LIKE '%world%'

问题区域：AND f.tag LIKE '%hello%' OR f.tag LIKE '%world%'

要意识到的重要一点是，'hello'和'world'可能并不总是在查询中。此外，可能还会增加3个搜索，但始终会搜索menu_item_id。

我不希望所有结果都需要每个f.tags，我只想让结果包含其中任何一个（OR）。

任何帮助都将不胜感激。

Answer 1

喜欢......括号？

SELECT t.*, u.username AS owner, uu.username AS replyname, a.location
FROM thread t
INNER JOIN filter_thread as ft ON t.thread_id = ft.thread_id
INNER JOIN filter as f ON f.filter_id = ft.filter_id
INNER JOIN users u ON t.owner_id = u.id 
INNER JOIN users uu ON t.last_post_id = uu.id
INNER JOIN user_profiles AS up ON u.id = up.user_id
INNER JOIN avatars AS a ON up.avatar_id = a.id
WHERE t.menu_item_id='1'
AND (
    f.tag LIKE '%hello%'
 OR f.tag LIKE '%world%'
)

如果问题是这个查询是动态制作的，只需在前面添加1即可。

Answer 2

使用括号指定AND和OR的优先顺序。

a AND (b OR c)

VS

(a AND b) OR c

例如：

WHERE t.menu_item_id='1'
  AND (    f.tag LIKE '%hello%'
        OR f.tag LIKE '%world%'
      )

这将仅返回具有menu_item_id ='1'AND的行，其中包含'hello'或'world'标记。

Answer 3

我不确定这是否能回答你的问题，但我喜欢使用括号来让事情更容易阅读，就像这样

SELECT t.*, u.username AS owner, uu.username AS replyname, a.location
FROM thread t
INNER JOIN filter_thread as ft ON t.thread_id = ft.thread_id
INNER JOIN filter as f ON f.filter_id = ft.filter_id
INNER JOIN users u ON t.owner_id = u.id 
INNER JOIN users uu ON t.last_post_id = uu.id
INNER JOIN user_profiles AS up ON u.id = up.user_id
INNER JOIN avatars AS a ON up.avatar_id = a.id
WHERE t.menu_item_id='1'
AND (f.tag LIKE '%hello%'
OR f.tag LIKE '%world%')

现在它说t.menu_item_id = 1并且括号中的任何一个条件都是真的，而不是说（t.menu_item_id = 1 AND f.tag LIKE'％hello％'）或者f.tag LIKE' ％世界％'

希望有所帮助。

Answer 4

为什么不使用括号？

WHERE t.menu_item_id='1' AND (f.tag LIKE '%hello%' OR f.tag LIKE '%world%')

Answer 5

这是通过PHP动态生成的最终代码：

    $sql_select = "SELECT t.*, u.username AS owner, uu.username AS replyname, a.location";
    $sql_from = " FROM ";
    $sql_where = " WHERE ";
    $sql_joins = "";
    $sql_order = " ORDER BY t.replystamp DESC
                    LIMIT $threadstart, $limit";  
    $sql_from .= ' thread t ';
    $sql_where .= " t.menu_item_id=$menu_item_id";
    $sql_joins .= ' INNER JOIN filter_thread as ft ON t.thread_id = ft.thread_id
                    INNER JOIN filter as f ON f.filter_id = ft.filter_id
                    INNER JOIN users u ON t.owner_id = u.id 
                    INNER JOIN users uu ON t.last_post_id = uu.id
                    INNER JOIN user_profiles AS up ON u.id = up.user_id
                    INNER JOIN avatars AS a ON up.avatar_id = a.id';
    if ($ac_total > 0) {
        $sql_where .= " AND (";
        for ($i=0; $i < $ac_total; $i++)
        {
            if ($i == 0)
            {
                $sql_where .= "f.tag LIKE '%$active_category[$i]%'";
            } else {
                " OR f.tag LIKE '%$active_category[$i]%')";
            }
        }
        $sql_where .= ")";
    }
    $sql = $sql_select . $sql_from . $sql_joins . $sql_where . $sql_order;
    $query = $this->db->query($sql);

感谢您的帮助！

除了多个OR之外，还需要WHERE AND子句

5 个答案: