Tables and relationships
Edit tables, columns, keys and relationships in logical and physical views.
Midnight ERD
Design relationships. Share the specifications.
Midnight ERD is a database design app for Apple silicon Mac. Import structure from MySQL, MariaDB, Microsoft SQL Server or PostgreSQL, edit the local model, and export diagrams and Excel specifications.
macOS · Apple silicon · MySQL, MariaDB, MSSQL and PostgreSQL schema import
Mac 1.0.1 available · DMG · Automatic updates
Import four database systems
Read schema structure from MySQL, MariaDB, Microsoft SQL Server (MSSQL) or PostgreSQL into a local project.
MySQL and MariaDB CREATE SQL
Generate CREATE SQL for all or selected tables, with options for DROP, IF NOT EXISTS, indexes, comments and foreign keys.
Diagrams and Excel specifications
Export PNG, SVG and PDF diagrams and Excel table specifications. Import and export dictionary entries, domains and .erd.json projects.
From database structure to a design you can share
Start with a model
Create tables, columns, keys and relationships, or import structure from one of the four supported database systems. Schema import reads structure without changing the source database.
Refine the design
Switch between logical and physical views and save the project on your Mac.
Export the result
Share diagrams as PNG, SVG or PDF, including multipage PDFs for large diagrams. Export an Excel specification with a cover, table list, definitions, columns and relationships.
Details to know
Schema import and SQL generation have different support
Schema import supports MySQL, MariaDB, Microsoft SQL Server (MSSQL) and PostgreSQL. CREATE SQL generation described here is for MySQL and MariaDB.
Dictionaries and domains
Export dictionary entries and domains to Excel, edit them and import them again. Review additions, changes and duplicates before applying the import.
Local MCP
Copy the configuration from MCP connection → Local MCP connection into a client that supports HTTP MCP. Keep Midnight ERD running on the same Mac to read and edit projects. AI features are provided by your compatible client.
Install and update
Open the Apple silicon DMG and drag the app into Applications. Version 1.0.1 checks for updates and downloads them automatically; quit the app to apply a downloaded update. You can also choose Help → Check for updates.
Upgrading from 1.0.0
Install the latest DMG once to enable automatic updates.
See it in use
A closer look
Install Midnight ERD
macOS · Apple silicon · MySQL, MariaDB, MSSQL and PostgreSQL schema import
Version 1.0.1