php - 使用 LEFT JOIN 计算行数

Question

我在使用 LEFT JOIN 计算行数时遇到问题.. 所以我有 2 个表(域、聊天)，我想提取每个域的聊天总数、打开聊天的数量和关闭聊天的数量。公共(public)列是“域”

这是我的代码:

$getDomains = $DB->query("
SELECT 
dom.id as domainID, dom.name as domainName, dom.domain as url, dom.gmt, dom.opening_hours, 
COUNT(t1.id) as chats, 
COUNT(t2.id) as opened_chats, 
COUNT(t3.id) as closed_chats

FROM domains dom

LEFT OUTER JOIN chat t1 ON t1.domain=dom.domain
LEFT OUTER JOIN chat t2 ON t2.domain=dom.domain AND t2.status=1
LEFT OUTER JOIN chat t3 ON t3.domain=dom.domain AND t3.status=3

WHERE dom.account_id = ".$userInfo['account_id']." GROUP BY dom.domain") or die (mysqli_error($DB));

在聊天栏中我有 6 个聊天(3 个打开，3 个关闭)。

而不是:

• 所有聊天:6
• 打开的聊天:3
• 已关闭的聊天:3

结果是:

• 所有聊天:54
• 打开的聊天:54
• 已关闭的聊天:54

有人可以帮助我吗？我不明白问题出在哪里......

非常感谢!

Answer 1

尝试下面的查询插入LEFT OUTER JOIN，

$getDomains = $DB->query("
    SELECT 
    dom.id as domainID, dom.name as domainName, dom.domain as url, dom.gmt, dom.opening_hours, 
    (select count(t1.id) from chat as t1 where t1.domain=dom.domain) as chats,
    (select count(t2.id) from chat as t1 where t2.domain=dom.domain AND t2.status=1) as opened_chats,
    (select count(t3.id) from chat as t1 where t3.domain=dom.domain AND t3.status=3) as closed_chats

    FROM domains dom

    WHERE dom.account_id = ".$userInfo['account_id']." GROUP BY dom.domain") or die (mysqli_error($DB));