Skip to content

Latest commit

 

History

History
78 lines (60 loc) · 2.53 KB

File metadata and controls

78 lines (60 loc) · 2.53 KB

中文文档

Description

Table: Users

+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| user_id       | int     |
| name          | varchar |
| mail          | varchar |
+---------------+---------+
user_id is the primary key for this table.
This table contains information of the users signed up in a website. Some e-mails are invalid.

 

Write an SQL query to find the users who have valid emails.

A valid e-mail has a prefix name and a domain where:

  • The prefix name is a string that may contain letters (upper or lower case), digits, underscore '_', period '.', and/or dash '-'. The prefix name must start with a letter.
  • The domain is '@leetcode.com'.

Return the result table in any order.

The query result format is in the following example.

 

Example 1:

Input: 
Users table:
+---------+-----------+-------------------------+
| user_id | name      | mail                    |
+---------+-----------+-------------------------+
| 1       | Winston   | [email protected]    |
| 2       | Jonathan  | jonathanisgreat         |
| 3       | Annabelle | [email protected]     |
| 4       | Sally     | [email protected] |
| 5       | Marwan    | quarz#[email protected] |
| 6       | David     | [email protected]       |
| 7       | Shapiro   | [email protected]     |
+---------+-----------+-------------------------+
Output: 
+---------+-----------+-------------------------+
| user_id | name      | mail                    |
+---------+-----------+-------------------------+
| 1       | Winston   | [email protected]    |
| 3       | Annabelle | [email protected]     |
| 4       | Sally     | [email protected] |
+---------+-----------+-------------------------+
Explanation: 
The mail of user 2 does not have a domain.
The mail of user 5 has the # sign which is not allowed.
The mail of user 6 does not have the leetcode domain.
The mail of user 7 starts with a period.

Solutions

SQL