Sngine MySQL Customization

I need a skilled PHP and MySQL developer to modify Sngine functions to tailor MySQL queries for user selection.

Key Features Needed:
- Modify Sngine functions to optimize MySQL queries for specific user selections.
- Ability to select users based on:
- User IDs
- Custom complex SQL queries

Ideal Skills and Experience:
- Proficiency in PHP and MySQL
- Experience with Sngine
- Strong SQL query writing skills
- Problem-solving and optimization expertise

Please provide examples of similar work done and your estimated timeline.