OVM-ERD

Generate automated Entity-Relationship Diagrams (ERDs), SQL queries, and validation reports from your dbt repository.

📌 Overview

ovm-erd is a Python package designed to simplify the visualization and validation of Data Vault (DV) structured databases using dbt repositories. Automatically generate ER diagrams in multiple formats (Graphviz, Mermaid, Draw.io), produce SQL queries, and validate your database metadata.

✨ Features

• Automated ER Diagrams: Generate clear diagrams in:

  • ✅ Graphviz (PNG format)
  • ✅ Mermaid (Markdown)
  • ✅ Draw.io (.drawio.xml and PNG formats)

• SQL Generation: Automatically build SQL queries based on your repository metadata.

• Metadata Validation: Verify your data vault entities and relationships with HTML validation reports.

• Easy-to-use CLI: Simple commands to automate common tasks.

🚀 Installation

OVM-ERD requires Graphviz to be installed locally. See https://graphviz.org/ for details.

Install via pip:

pip install ovm-erd

📚 Usage

CLI

Generate ER diagrams:

ovm-erd generate [graphviz|mermaid|drawio]

Generate ER diagrams with specific paths:

ovm-erd generate graphviz --path /your/output/path

Generate diagrams distinctly for each ensemble/tag:

ovm-erd generate drawio --distinct

Generate SQL queries for a specific ensemble:

ovm-erd sql --ensemble your_ensemble_name

Validate metadata and generate HTML report:

ovm-erd validate

Specify custom paths for validation reports:

ovm-erd validate --path /your/report/path

Python API

Use the package directly in Python:

from ovm_erd.repository_reader import build_metadata_dict
from ovm_erd.erd_graphviz import generate_graphviz

repository_path = "your/dbt/repo"
output_path = "output/graphviz"

metadata = build_metadata_dict(repository_path=repository_path)
generate_graphviz(metadata, output_dir=output_path)

You can specify paths dynamically by assigning them to variables, enhancing flexibility:

custom_repo_path = "/path/to/dbt/repository"
custom_output_path = "/path/to/output"

metadata = build_metadata_dict(repository_path=custom_repo_path)
generate_graphviz(metadata, output_dir=custom_output_path)

🎨 ERD Color Coding

• Hub: Light Blue (#D6EAF8)
• Satellite: Light Yellow (#FFFACD)
• Link: Light Red (#F5B7B1)

Run tests:

pytest tests/

Example output Graphviz

📄 License

GPL © Ferry Ouwerkerk / Data-Project BV