Find Users With Valid E-Mails
<p>Table: <code>Users</code></p>

<pre>
+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| user_id       | int     |
| name          | varchar |
| mail          | varchar |
+---------------+---------+
user_id is the primary key (column with unique values) for this table.
This table contains information of the users signed up in a website. Some e-mails are invalid.
</pre>

<p>&nbsp;</p>

<p>Write a solution to find the users who have <strong>valid emails</strong>.</p>

<p>A valid e-mail has a prefix name and a domain where:</p>

<ul>
	<li><strong>The prefix name</strong> is a string that may contain letters (upper or lower case), digits, underscore <code>&#39;_&#39;</code>, period <code>&#39;.&#39;</code>, and/or dash <code>&#39;-&#39;</code>. The prefix name <strong>must</strong> start with a letter.</li>
	<li><strong>The domain</strong> is <code>&#39;@leetcode.com&#39;</code>.</li>
</ul>

<p>Return the result table in <strong>any order</strong>.</p>

<p>The result format is in the following example.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> 
Users table:
+---------+-----------+-------------------------+
| user_id | name      | mail                    |
+---------+-----------+-------------------------+
| 1       | Winston   | winston@leetcode.com    |
| 2       | Jonathan  | jonathanisgreat         |
| 3       | Annabelle | bella-@leetcode.com     |
| 4       | Sally     | sally.come@leetcode.com |
| 5       | Marwan    | quarz#2020@leetcode.com |
| 6       | David     | david69@gmail.com       |
| 7       | Shapiro   | .shapo@leetcode.com     |
+---------+-----------+-------------------------+
<strong>Output:</strong> 
+---------+-----------+-------------------------+
| user_id | name      | mail                    |
+---------+-----------+-------------------------+
| 1       | Winston   | winston@leetcode.com    |
| 3       | Annabelle | bella-@leetcode.com     |
| 4       | Sally     | sally.come@leetcode.com |
+---------+-----------+-------------------------+
<strong>Explanation:</strong> 
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.
</pre>

[]
['Create table If Not Exists Users (user_id int, name varchar(30), mail varchar(50))', 'Truncate table Users', "insert into Users (user_id, name, mail) values ('1', 'Winston', 'winston@leetcode.com')", "insert into Users (user_id, name, mail) values ('2', 'Jonathan', 'jonathanisgreat')", "insert into Users (user_id, name, mail) values ('3', 'Annabelle', 'bella-@leetcode.com')", "insert into Users (user_id, name, mail) values ('4', 'Sally', 'sally.come@leetcode.com')", "insert into Users (user_id, name, mail) values ('5', 'Marwan', 'quarz#2020@leetcode.com')", "insert into Users (user_id, name, mail) values ('6', 'David', 'david69@gmail.com')", "insert into Users (user_id, name, mail) values ('7', 'Shapiro', '.shapo@leetcode.com')"]
[{"value": "mysql", "text": "MySQL", "defaultCode": "# Write your MySQL query statement below\n"}, {"value": "mssql", "text": "MS SQL Server", "defaultCode": "/* Write your T-SQL query statement below */\n"}, {"value": "oraclesql", "text": "Oracle", "defaultCode": "/* Write your PL/SQL query statement below */\n"}, {"value": "pythondata", "text": "Pandas", "defaultCode": "import pandas as pd\n\ndef valid_emails(users: pd.DataFrame) -> pd.DataFrame:\n    "}, {"value": "postgresql", "text": "PostgreSQL", "defaultCode": "-- Write your PostgreSQL query statement below\n"}]
{"mysql": ["Create table If Not Exists Users (user_id int, name varchar(30), mail varchar(50))"], "mssql": ["Create table Users (user_id int, name varchar(30), mail varchar(50))"], "oraclesql": ["Create table Users (user_id int, name varchar(30), mail varchar(50))"], "database": true, "name": "valid_emails", "pythondata": ["Users = pd.DataFrame([], columns=['user_id', 'name', 'mail']).astype({'user_id':'int64', 'name':'object', 'mail':'object'})"], "postgresql": ["\nCreate table If Not Exists Users (user_id int, name varchar(30), mail varchar(50))"], "database_schema": {"Users": {"user_id": "INT", "name": "VARCHAR(30)", "mail": "VARCHAR(50)"}}}
{"mysql": ["MySQL", "<p><code>MySQL 8.0</code>.</p>"], "mssql": ["MS SQL Server", "<p><code>mssql server 2019</code>.</p>"], "oraclesql": ["Oracle", "<p><code>Oracle Sql 11.2</code>.</p>"], "pythondata": ["Pandas", "<p>Python 3.10 with Pandas 2.2.2 and NumPy 1.26.4</p>"], "postgresql": ["PostgreSQL", "<p>PostgreSQL 16</p>"]}
['Database']