Skip to content

Filtering & Key Inference

Control which entities and model kinds appear in the diagram, and derive keys for keyless models.

Excluding Entities

Use --exclude to drop tables/entities from the diagram. Each pattern is a case-sensitive glob tested against both the class name and the table name — an entity is excluded if either matches. Any relationships pointing at an excluded entity are dropped too, so no dangling lines remain.

# Exclude all link tables (class names ending in "Link")
erdify ./src/database --exclude '*Link'

# Exclude by table name, with multiple patterns
erdify ./src/database --exclude audit_log 'tmp_*' Session

💡 Quote patterns containing * so your shell doesn't expand them.

Excluding by Path (--exclude-paths)

--exclude filters by name after parsing. To skip whole folders before the scan — e.g. so erdify never reads a virtualenv's third-party models.py — use --exclude-paths. Patterns are case-sensitive globs matched against each models.py path relative to the input or any single path segment.

# Skip migrations and a legacy app, anywhere in the tree
erdify ./backend --exclude-paths migrations legacy

# Precise path glob
erdify ./backend --exclude-paths 'apps/experimental/*'

By default erdify already auto-skips models.py under common non-project directories — site-packages, .venv, venv, env, virtualenv, node_modules, __pycache__, .git, .tox, .mypy_cache, .pytest_cache — so running on a Django project picks up only your own apps, not installed packages like django.contrib.*, constance or django_celery_beat. Pass --no-default-excludes to scan those directories too.

Filtering by Model Kind

Use --sources to restrict the diagram to specific model frameworks. By default all recognized kinds are drawn (sqlmodel, sqlalchemy, django, dataclass, pydantic). This is the precise alternative to --exclude when you want a pure DB-table ERD and don't want Pydantic DTOs or @dataclass query wrappers to leak in.

# Only real DB tables — drops Pydantic/dataclass models entirely
erdify ./src/database --sources sqlmodel sqlalchemy

# ORM tables plus your Pydantic schemas, but no dataclasses
erdify ./src/database --sources sqlmodel pydantic

💡 --sources filters by kind; --exclude filters by name. Combine them freely.

Inferring keys (--infer-keys)

Pydantic models and dataclasses have no database key concept. By default all fields are rendered as plain columns and relationships come only from nested model references. If your models follow a database-like naming convention, pass --infer-keys to derive keys from field names:

  • a field named id → primary key
  • a field named <x>_id → foreign key targeting table <x>
# Plain columns (default)
erdify ./src/schemas

# Infer PK/FK from id / <x>_id naming
erdify ./src/schemas --infer-keys

ℹī¸ --infer-keys only affects Pydantic/dataclass models. SQLModel and SQLAlchemy keys are always read from the explicit definitions and never overridden.