Drizzle

If you're using Drizzle ORM, you can automatically generate an ER diagram from your schema files. This page provides instructions and tips for generating an ER diagram in a Drizzle project.

Drizzle and Schema Files

Drizzle ORM defines database schemas using TypeScript files, typically located in files like src/db/schema.ts. The schema files use Drizzle's type-safe API to define tables, columns, relations, and constraints.

When using Liam CLI, specify --format drizzle and --input path/to/schema.ts as follows:

npx @liam-hq/cli erd build --format drizzle --input src/db/schema.ts

If the above command runs without issue, you should see an ER diagram generated.

Database Type Support

Drizzle support in Liam ERD automatically detects whether you're using PostgreSQL or MySQL based on your imports:

• PostgreSQL: Uses imports from drizzle-orm/pg-core (e.g., pgTable, pgEnum)
• MySQL: Uses imports from drizzle-orm/mysql-core (e.g., mysqlTable, mysqlEnum)

The parser supports common Drizzle features including tables, columns, relationships, indexes, and constraints. However, some advanced features like multiple database schemas may not be fully supported yet.

Under the Hood

Liam CLI analyzes your TypeScript schema files using a custom parser that:

• Automatically detects the database type (PostgreSQL or MySQL) from your imports
• Extracts table definitions, column types, and relationships
• Supports Drizzle-specific features like enums, indexes, and constraints
• Handles complex type definitions and default values

Note: Drizzle support is currently marked as experimental. While it works reliably for most use cases, please report any issues you encounter to help us improve the parser.