Crow’s-foot diagram

Cardinality made explicit: which side is one, which is many, and which is optional.

The code

import { RelationalDiagram } from 'ts-prorm-orm';

const svg = new RelationalDiagram({
  title: 'Blog cardinality',
  entities: [
    { name: 'User', columns: [
        { name: 'id', type: 'INTEGER', primaryKey: true },
        { name: 'email', type: 'VARCHAR(255)' },
      ] },
    { name: 'Post', columns: [
        { name: 'id', type: 'INTEGER', primaryKey: true },
        { name: 'title', type: 'VARCHAR(200)' },
        { name: 'authorId', type: 'INTEGER', foreignKey: true },
      ] },
    { name: 'Tag', columns: [
        { name: 'id', type: 'INTEGER', primaryKey: true },
        { name: 'slug', type: 'VARCHAR(60)' },
      ] },
  ],
  relationships: [
    { from: 'User', to: 'Post', type: 'one-to-many' },
    { from: 'Post', to: 'Tag',  type: 'many-to-many' },
  ],
}).generate();

What it produces

Generated by running the snippet above — this is the generator's real output,
rebuilt by scripts/build-diagram-examples.mjs, not a picture of it.

Use this when the question is how many, and the ER diagram when the question is what columns.

Saving it

generate() returns the SVG as a string; save(path) writes it straight to
disk.

diagram.save('docs/schema.svg');

Diagram generators — every generator and its options

Models — the definitions these are drawn from

Crow’s-foot diagram

The code#

What it produces#

Saving it#

Related reading#

The code

What it produces

Saving it

Related reading