Question

还在学习MySQL，所以请耐心等待。

所以我有两个表：lead，即：

id  dat          in_click_id 
55  2011-08-15      400 
10  2011-08-13      400
34  2011-08-13      420 
50  2011-08-12      420   
15  2011-08-14      425

第二个表名为in_clicks：

id    location    keyword
400     KS         word1  
410     CO         word2
415     LA         word2
420     CA         word2
425     FL         word3

所以我试图找出一个潜在客户是否与点击相关联。换句话说，我试图得到以下内容：

keyword     count(keyword)
word1        15
...          ...

所以关键字将是单词，第二列将来自该关键字的潜在客户总数。

由于数据在两个单独的表中，我需要使用join命令，但是我在实施它时遇到了一些问题。

这是我多次尝试中的一项，显然无效。

SELECT id, discriminator, create_date, in_click_id, COUNT(in_click_id) 
FROM leads 
WHERE create_date LIKE '%2011-08-17%' 
ORDER BY COUNT(in_click_id) DESC 
INNER JOIN in_click ON leads.in_click_id = in_clicks.id;

帮助！？

Answer 1

您需要使用GROUP BY，如下所示：

SELECT leads.id, COUNT(in_click_id) 
FROM leads 
INNER JOIN in_click ON leads.in_click_id = in_clicks.id
WHERE create_date LIKE '%2011-08-17%'
GROUP BY leads.id
ORDER BY COUNT(in_click_id) DESC

Answer 2

您的SQL子句被错误排序。典型的SQL查询采用以下格式

SELECT ...
FROM ...
    {joins}
WHERE ...
GROUP BY ...
HAVING ...
ORDER BY ...
LIMIT ...

对于您的查询，您可能需要尝试以下内容，以计算与每个关键字相关联的潜在客户记录数。

SELECT c.keyword, count(l.id) 
FROM in_click c
    INNER JOIN leads l ON l.in_click_id = c.id   
GROUP BY c.keyword
ORDER BY COUNT(l.id) DESC

Answer 3

您需要使用Group By关键字：

SELECT in_clicks.keyword, COUNT(leads.in_click_id) 
FROM in_clicks  
INNER JOIN leads 
    ON leads.in_click_id = in_clicks.id
GROUP BY in_clicks.keyword
ORDER BY COUNT(leads.in_click_id)

使用count（）时连接两个单独的列

3 个答案: