paulzuradzki / schema-and-erd-demo

A demonstration of schema creation and entity relationship diagramming with Python SQLAlchemy.

Demo: Schema Creation and Entity Relationship Diagramming

Setup

Use Python 3.11. You may have dependency issues with pygraphviz library on 3.10.

# first, clone repo and navigate to root
python3 -m venv venv
source venv/bin/activate
python -m pip install --upgrade pip
python -m pip install -r requirements.txt

Usage

python src/export_schema.py

This will create a directory '/out' and create 5 files.

• erd.er
• erd.md
• erd.pdf
• schema.xlsx
• sql_ddl.sql

Terms

• schema - A general term for a specification of how data is or will be organized. A schema may also specify vocabulary, syntax, data types, attributes, value ranges, constraints, etc. SQLAlchmey uses the term metadata in a similar sense as schema.
• entity relationship model - An entity–relationship model (or ER model) describes interrelated things of interest in a specific domain of knowledge. A basic ER model is composed of entity types (which classify the things of interest) and specifies relationships that can exist between entities (instances of those entity types).