Documentation

Complete guide to using Schemer for database schema documentation.

Quick Start

Generate documentation for your database in seconds using Docker:

DATABASE_URL=postgres://user:password@localhost:5432/mydb \
docker run -e DATABASE_URL \
--net host -v $(pwd):/public \
dbschemer/schemer:latest \
schemer generate

Open public/index.html in your browser to view the generated documentation.

Supported Databases

PostgreSQL

postgres://user:pass@host:5432/db

MySQL

mysql://user:pass@host:3306/db

SQL Server

mssql://user:pass@host:1433/db

Cloud Spanner

spanner://projects/p/instances/i/databases/d

Command-Line Options

--output-dir

Specify where to save generated files (default: ./public)

schemer generate --output-dir /var/www/docs

--open

Automatically open the generated documentation in your browser

schemer generate --open

--graph-depth

Control relationship depth in ER diagrams (default: 3)

schemer generate --graph-depth 2

--graph-columns-display-regex

Filter which columns appear in diagrams using regex

schemer generate --graph-columns-display-regex "^(id|name|email)$"

--filter-tables

Include only specific tables

schemer generate --filter-tables "users,orders,products"

--filter-schemas

Include only specific schemas

schemer generate --filter-schemas "public,analytics"

--comment-format

Set comment rendering format (plain, markdown, asciidoc)

schemer generate --comment-format markdown

Common Use Cases

CI/CD Integration

Generate documentation automatically in your pipeline:

docker run -e DATABASE_URL \
--net host -v $(pwd):/public \
dbschemer/schemer:latest \
schemer generate

Hosting on GitHub Pages

Deploy generated docs directly:

schemer generate --output-dir ./docs
git add docs
git commit -m "Update schema docs"
git push

Large Database Optimization

For databases with many tables, reduce graph depth and filter columns:

schemer generate \
--graph-depth 1 \
--graph-columns-display-regex "^(id|.*_id)$"

Output Format

Schemer generates a complete static website including:

  • Database overview - High-level statistics and schema list
  • Table pages - Detailed column information, indexes, and constraints
  • Interactive ER diagrams - Visual relationship exploration
  • Search functionality - Find tables and columns quickly
  • Dark mode support - Comfortable viewing in any environment

Need Help?

For issues, questions, or feature requests: