+-----------------+---------+
| Column Name     | Type    |
+-----------------+---------+
| user_id         | int     |
| email           | varchar |
+-----------------+---------+
(user_id) is the unique key for this table.
Each row contains a user's unique ID and email address.

Input:

Users table:

+---------+---------------------+
| user_id | email               |
+---------+---------------------+
| 1       | alice@example.com   |
| 2       | bob_at_example.com  |
| 3       | charlie@example.net |
| 4       | david@domain.com    |
| 5       | eve@invalid         |
+---------+---------------------+

Output:

+---------+-------------------+
| user_id | email             |
+---------+-------------------+
| 1       | alice@example.com |
| 4       | david@domain.com  |
+---------+-------------------+

Explanation:

• alice@example.com is valid because it contains one @, alice is alphanumeric, and example.com starts with a letter and ends with .com.
• bob_at_example.com is invalid because it contains an underscore instead of an @.
• charlie@example.net is invalid because the domain does not end with .com.
• david@domain.com is valid because it meets all criteria.
• eve@invalid is invalid because the domain does not end with .com.

Result table is ordered by user_id in ascending order.