Entity-Relationship Diagram
PROModel your data as a clean ERD with keys and cardinality.
Produce an Entity-Relationship Diagram (ERD) from a described data model — entities, attributes, primary/foreign keys, and relationships with crow's-foot cardinality — as editable Mermaid source, following disciplined layout. Use when asked to model data, draw an ERD, design a schema, or show tables and their relationships.
Ask for it in plain English, e.g.
Works in
You ask: Draw an ERD for a simple booking system: Customers make Bookings; each Booking is for one Room on a set of Dates; a Room belongs to a Property; a Property has many Rooms. Customers can review Properties they've booked. Show keys and cardinality.

Example output shown for illustration. Your assistant produces this live from your own request once the skill is installed.