quick-erd

quick and easy text-based ERD editor with drag and drop visualization + code generator for migration, query, typescript types and orm entity

Quick Reference

Web UI Diagram and Editor

Hosted Web UI: https://quick-erd.surge.sh

Run locally (with access to local erd.txt file):

npm i -D quick-erd
npx erd-ui

npx cli

generate incremental migration: auto-migrate

generate typescript types of each table: erd-to-types

generate each table types and better-sqlite3-proxy schema: erd-to-proxy

generate java jpa entities and repositories: erd-to-spring

generate initial schema: erd-to-sqlite, erd-to-knex

reverse-engineer erd text: pg-to-erd, mysql-to-erd, mssql-to-erd, sqlite-to-erd

format erd text: format-erd

open web ui: erd-ui

Features

• text-based erd editor
• import from existing postgresql schema
• generate database schema migration
  • knex migrate script
  • sqlite migrate statements
  • support postgres, mysql, mssql, sqlite
• published as npx script
• web-based schema visualization
  • zoom in/out
  • drag-and-drop moving
  • show/hide non-relational columns
  • custom heading color per table
  • customize UI color theme
  • keyboard shortcuts
  • auto save-and-restore with localStorage
  • auto format the schema text
  • auto normalize specified column
  • auto avoid table overlapping visually
  • import/export diagram with drag position and zoom level
  • right-click on diagram to select table/column in editor
  • auto-complete when creating new table
• web-based query builder
  • select columns with checkbox
  • generate SQL/knex query with nested join-table
  • generate typescript type of query result
  • copy selected part into clipboard
  • support additional query (where / group-by / order-by / limit, e.t.c.)
  • support sharing diagram embedded in url
• local web-ui
  • offline usage
  • load from disk file
  • save to disk file

Usage

ERD Editing

Option 1: Run it online

Hosted on https://erd.surge.sh and https://quick-erd.surge.sh

Option 2: Run it locally

1. Clone this git repository
2. cd into the folder
3. Run npm install
4. Run npm start

Database Utility

Setup

1. Install this package as devDependency, run npm i -D quick-erd

2. Setup database connection credential in .env.

.env is not needed for sqlite

You can refer to .env.example

Overview of Commands

Below are available commands in example.

Remarks to Windows user (click to expand)

Windows users area recommended to use git bash to perform pipe operations.

If you prefer to use PowerShell, you may need to replace < with \< to pipe file content as stdin.

To reverse-engineer erd file from live database:

• npx pg-to-erd > erd.txt
• npx mysql-to-erd > erd.txt
• npx mssql-to-erd > erd.txt
• npx sqlite-to-erd dev.sqlite3 > erd.txt

To generate initial database migration script from erd file:

• npx erd-to-knex pg < erd.txt > migrations/001-create-tables.ts
• npx erd-to-sqlite < erd.txt > migrations/001-create-tables.sql

To generate incremental database migration script from erd file and live database:

• npx auto-migrate pg < erd.txt
• npx auto-migrate mysql < erd.txt
• npx auto-migrate mssql < erd.txt
• npx auto-migrate dev.sqlite3 < erd.txt
• npx auto-migrate --rename pg < erd.txt

To generate typescript types of each table:

• npx erd-to-types < erd.txt > types.ts

To generate types and proxy schema for better-sqlite3-proxy:

• npx erd-to-proxy < erd.txt > proxy.ts
• npx erd-to-proxy --factory < erd.txt > proxy.ts

To generate java jpa entities and repositories:

• npx erd-to-spring pg < erd.txt
• npx erd-to-spring h2 < erd.txt

To format erd file:

• npx format-erd erd.txt
• npx format-erd --ref ordered_erd.txt new_erd.txt

To update erd file from live database:

npx pg-to-erd > erd.tmp
npx format-erd -r erd.txt erd.tmp
meld erd.txt erd.tmp
rm erd.tmp

To open web ui with disk file access:

• npx erd-ui
• npx erd-ui -p 8520 erd.txt

Import from Existing Schema

1. Extract from live database

For Postgresql schema: Run pg-to-erd

For Mysql/MariaDB schema: Run mysql-to-erd

For MSSQL (Microsoft SQL Server) schema: Run mssql-to-erd

For Sqlite schema: Run sqlite-to-erd SQLITE_FILENAME

You can save the output into a file using pipe. e.g. by running: pg-to-erd > erd.txt

2. Copy the output text into the web erd editor

Export as Migration Script

You can export the erd.txt to a database migration script. This process is also called forward-engineering for database schema.

Supported schema format includes: knex and better-sqlite3-helper

Export as Knex Migration Script

1. Run erd-to-knex pg < erd.txt > migrate.ts

You need to specify the db_client. e.g. pg, mysql, mssql, or sqlite

You can save the erd text into a file, then load it as stdin. e.g. erd-to-knex pg < erd.txt

Also, you can save the result into a knex migration script. e.g.

# create migrations directory if not exist
mkdir -p migrations

# read from erd.txt, save to migrations/YYYYmmddHHMMSS-create-tables.ts
erd-to-knex pg < erd.txt > migrations/$(date +"%Y%m%d%H%M%S")-create-tables.ts

Export as Sqlite Migration Script

1. Run erd-to-sqlite < erd.txt > migrate.sql

Depending on your migration directory (default is ./migrations/), you may save the migration script in corresponding directory. e.g.

# create migrations directory if not exist
mkdir -p migrations

# read from erd.txt, save to migrations/000-create-tables.sql
erd-to-sqlite < erd.txt > migrations/000-create-tables.sql

Generate Incremental Knex Migration Script

1. Run npx auto-migrate dev.sqlite3 < erd.txt

   or npx auto-migrate mysql < erd.txt

   or npx auto-migrate mssql < erd.txt

   or npx auto-migrate pg < erd.txt

   or npx auto-migrate --rename pg < erd.txt

This command auto setup knex and npm scripts, then it generates incremental migration script for knex.

For sqlite database, it also auto setup db.ts with better-sqlite3 connection using given database filename.

The --rename or -r flag enable table/column rename detection.

If there are pending knex migrations not applied, it will show error message and stop running.

Generate typescript types of each table

1. Run npx erd-to-types < erd.txt > types.ts

This command generates the the typescript types of each table.

The relation fields are also included based on the foreign key references.

Generate types and proxy schema for better-sqlite3-proxy

1. Run npx erd-to-proxy < erd.txt > proxy.ts

This command generates the typescript types of each table and the schema for proxySchema() in better-sqlite3-proxy

The relation fields are also included based on the foreign key references.

Additional arguments:

• export format:

  • --factory
  • --singleton (default)

• import format:

  • --commonjs or --cjs (default)
  • --module or --esm

Export Format:

The default behavior is to generate a proxy as singleton with commonjs format.

If a factory function is preferred, you can pass --factory in the argument, e.g. npx erd-to-proxy --factory < erd.txt > proxy.ts

Import Format:

In commonjs mode, the import path of local typescript files should not include .js extension; In esm module, the import path of local files should include .js extension.

In the generated proxy file, it needs to import the local file db.ts. This tool will try to read the type field in package.json to determine the import format, and fallback to use "commonjs" format if undetermined.

If esm format is preferred but undetected, you can pass --esm in the argument, e.g. npx erd-to-proxy --esm < erd.txt > proxy.ts

Format Diagram Text

To "prettify" the erd, run: format-erd erd.txt

To sort the tables and fields of exported erd according to previous version of erd, run: format-erd --ref old_erd.txt new_erd.txt

The original text file will be backup with suffix, e.g. 'erd.txt.bk_20220212144828'

The formatted erd text will be saved in-place.

Warning: Comments are not preserved in the current version. If you want to restore the comments, you may use diff tools like meld to compare the formatted version and original version.

Todo

• to support composite primary keys

• to support composite unique keys

• update "auto place" algorithm to avoid relationship lines overlap the tables visually

License

This project is licensed with BSD-2-Clause

This is free, libre, and open-source software. It comes down to four essential freedoms [ref]:

• The freedom to run the program as you wish, for any purpose
• The freedom to study how the program works, and change it so it does your computing as you wish
• The freedom to redistribute copies so you can help others
• The freedom to distribute copies of your modified versions to others