Find Valid Emails: simple solution using REGEXP. ✅
IntuitionThe goal is to identify valid email addresses within a database. A valid email address should contain exactly one @ symbol, with the part before the @
# Intuition
The goal is to identify valid email addresses within a database. A valid email address should contain exactly one @ symbol, with the part before the @ containing only alphanumeric characters and underscores. The domain part should start with a letter and end with .com.

# Approach
**Pattern:** `^[0-9a-zA-Z_]+@[a-zA-Z][a-zA-Z]*\\.com$`
<br>
- `^` asserts the position at the start of the string.  <br>
- `[0-9a-zA-Z_]+` matches one or more alphanumeric characters or underscores before the `@` symbol. <br>                     
- `@` matches the `@` symbol exactly.  <br>
- `[a-zA-Z]` ensures that the domain part starts with a letter.  <br>
- `[a-zA-Z]*` matches zero or more letters following the initial letter in the domain.  <br>
- `\.com` matches the exact string `.com`.  <br>
- `$` asserts the position at the end of the string.  


# Complexity
- Time complexity:
<!-- Add your time complexity here, e.g. $$O(n)$$ -->

- Space complexity:
<!-- Add your space complexity here, e.g. $$O(n)$$ -->

# Code
```mysql []
# Write your MySQL query statement below
select *
from Users
where email regexp '^[0-9a-zA-Z_]+@[a-zA-Z][a-zA-Z]*\\.com
```
order by user_id
```
['MySQL']