SQL计算不同的电子邮件域

Question

我正在尝试计算不同电子邮件域的电子邮件地址数量。

name     | email
---------+----------------------
Jack     | jack@email.com
John     | john@something.com
Mike     | mike@email.com

结果应该是

domain        | count
--------------+-----------------
email.com     | 2
something.com | 1

Answer 1

在sql server中，您可以使用：SQL HERE

select email, count(*) from (
    SELECT SUBSTRING(email, CHARINDEX('@', email) + 1, 255) email from yourtable
) as T group by email

您可以在MySQL中尝试：SQL HERE

select email, count(*) from (
    SELECT SUBSTRING(email, locate('@', email) + 1, 255) email from Table1
) as T group by email

Answer 2

在 MySQL 中，您可以使用以下查询

SELECT SUBSTRING_INDEX(email, '@', -1) AS 'domain',
       COUNT(*) AS 'count'
FROM table1
GROUP BY domain;

<强>输出

|     domain    | count |
|---------------|-------|
|     email.com |     2 |
| something.com |     1 |

在此处测试此查询 MySQL Demo