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3 templates · ERD

Database Design ER Diagram Examples

ER diagrams are the blueprint of a database — every table, column type, primary key, foreign key, and relationship constraint in one view.

Standard Chen 1976 / Everest 1976 (crow's foot)Engine schematex-erdExport SVG · PNG · PDF
3 templates
ERD Database Design ER
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Nothing close enough? Start from a blank erd → Describe it in one paragraph.

How to

How to use an erd template.

  1. 01List the tables

    Name each table and its primary key — the AI creates the entity boxes.

  2. 02Add columns and types

    Describe the important columns with their data types (int, varchar, timestamp, boolean) and any unique or not-null constraints.

  3. 03Define foreign keys

    Say which column in one table references which table — the AI draws the FK lines and adds cardinality notation.

  4. 04Review and export

    Check that the cardinality (one-to-many, many-to-many) is correct, then export as PNG/SVG or share for schema reviews.

FAQ

Questions about erd templates

What is an ER diagram?

A diagram that represents a database schema: tables as entities, columns as attributes, and relationships (with PK/FK constraints) as connecting lines. It is the standard tool for designing and communicating database structures.

Which notation does ChatDiagram use for ER diagrams?

ChatDiagram uses crow's foot notation (the standard for database design), which shows cardinality (one/many) and optionality (mandatory/optional) at each end of a relationship line.

Can I generate a diagram from an existing SQL schema?

Yes — paste your CREATE TABLE statements and the AI extracts the tables, columns, and foreign keys into an ER diagram automatically.