MyMapDatabase schema for a SaaS app with users, orgs, projects...
01
Describe entities and rules
Name the things being stored and how they relate in the application.
ER Diagram Maker with AI
Describe your database entities, tables, or data model and AI builds an ER diagram — tables, columns, primary keys, and relationships.
Free to startNo credit card requiredPDF, docs & images supported
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ER Diagram Maker with AI
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Templates made with this tool
Real prompts and the maps that came back. Open one to see the whole board and remix the prompt.
Hospital Management System ER Diagram
Create an ER diagram for a hospital management system with Patient, Doctor, Appointment, Department, and Medical Record entities
Hospital Database DesignLibrary Management System ER Diagram
Create an ER diagram for a library management system
Library Database DesignSchool Management System ER Diagram
Create an ER diagram for a school management system with Student, Teacher, Course, Enrollment, and Grade entities
School database designPrompts to start from
Click one to fill the box above. Edit anything before you send.
How to draft an ER diagram
No template to fill in and no drawing. You talk; the canvas keeps up.
02
Specify identifiers and cardinality
Provide keys, important attributes, and whether each relationship is optional or required.
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03
Walk through sample records
Check that the model can represent real cases without duplicate or impossible relationships.
A visual model of stored relationships
An entity-relationship diagram shows entities, their attributes, and the relationships between them. At a relational design level, it can also identify tables, primary keys, and foreign keys.
Review a data model before implementation
Use it to discuss requirements or explain an existing schema. The SaaS example links users and organizations through memberships and includes projects and subscriptions.
Make the business rules visible
- Choose the modeling level. Distinguish a conceptual entity model from a table-level schema.
- Give entities stable identifiers. Names alone may not uniquely identify records.
- State minimum and maximum cardinality. Optional and mandatory relationships are different constraints.
- Resolve many-to-many relationships deliberately. A relational schema usually represents them with an association table.
- Test realistic edge cases. Check repeated memberships, empty collections, and historical records where relevant.
Sketch and revise the model
MyMap turns your entities and rules into a diagram for discussion. Ask to add a relationship or revise cardinality; the visual does not itself create tables or enforce constraints.
Export and share
PNG and PDF
Whole map or one frame. PDF and clean PNG on Pro.
Slides
Ask for slides from this map and present frame by frame.
Share a link
A read-only link for anyone; they can copy it to their own canvas.
Keep editing
Every map stays on your canvas; come back and ask for more.
Common questions
Does generating a diagram create a database?
No. The diagram is a design artifact. Database implementation requires separate schema definitions and migrations.
Can it show many-to-many relationships?
Describe the relationship and your modeling level. For a relational schema, request an association entity with the relevant foreign keys.
Should I include every column?
Include enough detail for the review. A high-level discussion may need only entities and relationships; implementation planning may require keys and important constraints.
How do I use an ER diagram maker?
List your entities, their key fields and how each pair relates, including one-to-many or many-to-many cardinality. Paste the list into the chat and ask for an ER diagram, then check the keys and relationship directions against your requirements.
How do I prompt an ER diagram generator AI?
Specify whether you want a conceptual model or a relational schema, then describe the entities and business rules. For a relational many-to-many relationship, request a junction table and name its foreign keys; review the result before writing migrations.
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ER Diagram Maker with AI
Free to start. No credit card required.
✦ Free to start · No credit card required · PDF, docs & images supported