DATABASE_SCHEMA.md

Database Schema

This document outlines the data structures used within the application, including local storage and remote database models.

📱 Local Storage (AsyncStorage)

The application uses AsyncStorage for persisting simple data on the device.

Key	Type	Description
user_token	String	JWT token for authentication.
theme_preference	String	User's preferred theme ('light' or 'dark').
onboarding_complete	Boolean	Flag to track if user has seen onboarding.

🗄 Remote Database (Example: PostgreSQL/Mongo)

The backend API is backed by a relational database. Below is the simplified schema.

Tables / Collections

Users

Stores user account information.

• id (UUID, Primary Key)
• email (String, Unique)
• password_hash (String)
• full_name (String)
• created_at (Timestamp)

Products

Catalog of coffee items.

• id (UUID, Primary Key)
• name (String)
• description (Text)
• price (Decimal)
• category (String)
• image_url (String)

Orders

Customer orders.

• id (UUID, Primary Key)
• user_id (UUID, Foreign Key -> Users.id)
• status (Enum: 'pending', 'completed', 'cancelled')
• total_amount (Decimal)
• created_at (Timestamp)

OrderItems

Items within an order.

• id (UUID, Primary Key)
• order_id (UUID, Foreign Key -> Orders.id)
• product_id (UUID, Foreign Key -> Products.id)
• quantity (Integer)
• price_at_purchase (Decimal)

🔗 Relationships

• Users 1:N Orders
• Orders 1:N OrderItems
• Products 1:N OrderItems

🔍 Indexing Strategy

• Index on Users.email for fast lookups during login.
• Index on Orders.user_id for retrieving user history.
• Index on Products.category for filtering.