Users and Orders ER diagram models a foundational e-commerce relational schema with two entities: Users (storing identity, contact, and authentication) and Orders (capturing order details linked to users via foreign key). The users table enforces unique constraints on phone and email, while orders references users through user_id as a foreign key, establishing a one-to-many relationship. This schema pattern demonstrates proper normalization, referential integrity, and constraint design essential for transactional systems handling customer data and order fulfillment. Fork and customize this diagram on Diagrams.so to adapt it for your application's specific fields, add indexes, or extend with additional entities like products or payments.