我正在使用mysql,这是我拥有的架构。
第一张桌子:Keywords
+------------+-------------+
| keyword_id | keyword_tag |
+------------+-------------+
| 2 | marketing |
| 58 | sales |
| 59 | scraping |
| 1 | seo |
| 3 | testkeyword |
+------------+-------------+
第二张表:Domains
+-----------+-----------------+---------------+---------------------+-----------------+
| domain_id | domain_name | campaign_name | campaign_date | campaign_note |
+-----------+-----------------+---------------+---------------------+-----------------+
| 1 | test.org | campaign 1 | 2019-08-27 17:10:58 | Test |
| 11 | example.org | campaign 2 | 2019-08-27 17:36:06 | Campaign Note 2 |
+-----------+-----------------+---------------+---------------------+-----------------+
第三张表:Domain_Keywords
+-------+-----------+------------+
| dk_id | domain_id | keyword_id |
+-------+-----------+------------+
| 1 | 1 | 1 |
| 2 | 1 | 2 |
| 3 | 1 | 3 |
| 4 | 11 | 1 |
| 5 | 11 | 2 |
| 6 | 11 | 58 |
| 7 | 11 | 59 |
+-------+-----------+------------+
第四张表:Emails
+----------+-----------------------+-------+--------------+-------+----------------+-----------+---------+
| email_id | email | valid | is_generated | score | number_results | domain_id | user_id |
+----------+-----------------------+-------+--------------+-------+----------------+-----------+---------+
| 1 | b1@test.org | 1 | 1 | 0.5 | 2 | 1 | 3 |
| 2 | b2@test.org | 1 | 1 | 0.3 | 0 | 1 | 1 |
| 3 | a1@example.org | 1 | 1 | 0.3 | 0 | 11 | 4 |
| 4 | a2@example.org | 1 | 1 | 0.3 | 0 | 11 | 4 |
| 5 | a3@example.org | 1 | 1 | 0.3 | 0 | 11 | 1 |
| 6 | a4@example.org | 1 | 1 | 0.5 | 3 | 11 | 3 |
+----------+-----------------------+-------+--------------+-------+----------------+-----------+---------+
请指导我如何从这四个表中查询数据。谢谢
答案 0 :(得分:2)
由于给定的domain_id
在每个表中可以有多行,因此有必要在派生表中执行所有聚合,然后将它们联接到Domains
表中。
SELECT d.campaign_name,
d.campaign_date,
COALESCE(e.num_emails, 0) AS num_emails,
COALESCE(e.num_generated_emails, 0) AS num_generated_emails,
k.keywords
FROM Domains d
JOIN (SELECT dk.domain_id,
GROUP_CONCAT(k.keyword_tag) AS keywords
FROM Domain_Keywords dk
JOIN Keywords k ON k.keyword_id = dk.keyword_id
GROUP BY dk.domain_id) k ON k.domain_id = d.domain_id
LEFT JOIN (SELECT domain_id,
COUNT(*) AS num_emails,
SUM(is_generated) AS num_generated_emails
FROM Emails
GROUP BY domain_id) e ON e.domain_id = d.domain_id
输出:
campaign_name campaign_date num_emails num_generated_emails keywords
campaign 1 2019-08-27 17:10:58 2 2 seo,marketing,testkeyword
campaign 2 2019-08-27 17:36:06 4 4 seo,marketing,sales,scraping
答案 1 :(得分:1)
您可以尝试一下。简单的inner join
和group by
子句将为您提供所需的结果。只是Group_Concat
用于将您的城市名称转换为一个字符串,count
用于计数电子邮件记录。
您可能会发现Link的这种提琴是有效的。
select Domains.campaign_name, Domains.campaign_date, tab2.countemail as Found, tab2.countemail as generate, tab1.KeyTag
from Domains inner join
(select Domains.domain_id, group_concat(Keywords.keyword_tag) as KeyTag
from Domains
inner join Domain_Keywords on Domains.domain_id = Domain_Keywords.domain_id
inner join Keywords on Domain_Keywords.keyword_id = Keywords.keyword_id group by Domains.domain_id ) as tab1
on Domains.domain_id = tab1.domain_id
inner join
( select Domains.domain_id, Count(Emails.is_generated) as countemail
from Domains
inner join Emails on Domains.domain_id = Emails.domain_id
group by Domains.domain_id
) as tab2
on Domains.domain_id = tab2.domain_id
```