Entity-relationship model for a student registration system with five core entities: STUDENT, REGISTRATION, ATTACHMENT, DOCUMENT, and ADMINISTRATOR. Students create multiple registrations and documents, each registration links to one attachment (company placement details), and administrators manage registration workflows. The SYSTEM entity enforces security levels and maintains validation logs across student records. This normalized schema supports academic institutions tracking student enrollments, internship placements, and document submissions. Fork this ER diagram on Diagrams.so to customize entities, add attributes, or export as .drawio for database design tools.