Simple ER Diagram Generator
Visualize your database schema instantly. Generate Entity-Relationship diagrams from text or templates. Includes 20+ standard data patterns (E-commerce, Auth, etc.).
About
A well-structured database is the backbone of any robust application. Jumping into code without a visual map often leads to 'spaghetti schemas'—inconsistent naming, redundant columns, and missing foreign keys. This Simple ER Diagram Generator allows you to rapidly prototype table structures and relationships before you write a single line of SQL.
Use the preset templates to load common architectures (like standard User Authentication or Shopping Cart systems) and modify them to fit your specific needs.
Formulas
This tool visualizes relationships based on standard database normalization principles.
- Step 1: Entity Identification. Nouns in your business logic become tables (e.g., 'Customer', 'Product').
- Step 2: Attribute Mapping. Adjectives become columns (e.g., 'Price', 'Email').
- Step 3: Relationship Definition. Verbs define the links. If Entity A has many Entity B, a Foreign Key is placed on Entity B pointing to A.
Reference Data
| Cardinality | Symbol | Meaning |
|---|---|---|
| One-to-One | Line with two perpendicular marks | A User has one Profile; a Profile belongs to one User. |
| One-to-Many | Crow's Foot | A Customer places many Orders. |
| Many-to-Many | Double Crow's Foot | Students enroll in Courses (requires a join table). |
| Zero-to-Many | Circle + Crow's Foot | A User may have zero or multiple comments. |