What's inside

This chapter covers the core features and capabilities of Data Modeling Patterns.

What's inside

• 9 runnable SQL files — dimensional models, all the SCD types, audit columns,

soft delete, partitioning, a full normalization walk-through, and a complete

worked e-commerce schema.

• 6 decision guides — each with quick-reference tables, an explicit decision

tree, and an FAQ, so you can choose correctly under time pressure.

• A worked example — one coherent e-commerce OLTP schema with an

entity-relationship diagram and design rationale that ties every pattern together.

All SQL is PostgreSQL syntax with notes where other engines differ. No external

dependencies — you need only a database to run it against (or just read it).

Quick start

1. Unzip the product.

2. Skim this README, then open examples/ecommerce-er-diagram.md

for the big picture.

3. Run a pattern against a scratch database, e.g.:

   psql "postgres://localhost/scratch" -f sql/normalization-examples.sql
   psql "postgres://localhost/scratch" -f sql/scd-type2.sql
   psql "postgres://localhost/scratch" -f examples/ecommerce-model.sql

Each file is self-contained: it creates its own schema, seeds demo data, and

ends with verification queries (commented) you can run to see the result.

4. Read the matching guide in docs/ for the *why* and the decision rules.

The SQL files create schemas named dw, app, norm, and shop. Run them on

a throwaway database so they never touch anything real.

File-by-file guide

Follow this guide to get Data Modeling Patterns up and running in your environment.

File-by-file guide

sql/ — runnable patterns

docs/ — decision guides

examples/ — a complete worked model

How to use this product

Designing a new schema? Start with anti-patterns.md

(know what to avoid), then normalization-vs-denormalization.md

to set your target normal form, then build with

ecommerce-model.sql as a template.

Building a warehouse / reporting layer? Read

star-vs-snowflake.md, model with

star-schema.sql, and handle changing dimensions with

scd-types.md + scd-type2.sql.

Performance problem on an existing schema? Go straight to

indexing-strategy.md, and consider

partitioning-guide.md if the table is large with a

date/lifecycle pattern.