Why I Chose pgAdmin as a SQL Diagram Tool (ERD)

January 18, 2026 - Reading time: 15 minutes

When I design a database schema, I always want a diagram (ERD).
It helps me see the system, understand relationships, and avoid mistakes early.

I tested several tools, and each one had strengths — but I ended up choosing pgAdmin because it matches how I work: visual first, direct PostgreSQL connection, no extra services.

Free ERD tools I tried (or considered):

 

dbdiagram.io (free tier, web-based)

Pros

• Very clean UI
• You write a small DSL (text schema), and it visualizes it
• Can export SQL

Cons

• Requires learning the DSL
• Free tier has diagram/project limits

Good if you like “schema as code” + clean visuals.

 

Diagrams.net (Draw.io) (free, offline or web)

Pros

• Fully free
• Great for planning and presenting diagrams

Cons

• Not a database tool
• No SQL export, no constraints, no validation

Good if you only need a visual plan and write SQL manually.

 

ERDPlus (free, web-based)

Pros

• Focused on ER diagrams
• Can generate SQL
• Great for simple designs and learning

Cons

• Basic interface
• Not many advanced features

Good if you want quick diagrams + SQL export for small projects.

 

DBeaver Community (free, desktop)

Pros

• Free and powerful DB client
• Can create ER diagrams from an existing schema
• Works with PostgreSQL, MySQL, and many others

Cons

• Diagrams are good, but not always “presentation perfect”

Good if you want a free alternative to DataGrip with ERD support.

 

MySQL Workbench (free, desktop)

Pros

• Classic tool for MySQL diagrams
• Supports reverse engineering from a live database

Cons

• Mostly MySQL-focused (not ideal if your main DB is PostgreSQL)

  

Oracle SQL Developer Data Modeler (free, desktop)

Pros

• Free graphical data modeling tool
• Supports logical + relational models and forward/reverse engineering

Cons

• Can feel heavy if you just want quick diagrams

Good if you want “serious” data modeling features for free.

 

pgModeler (open-source PostgreSQL modeler)

Pros

• Designed specifically for PostgreSQL
• Open-source and cross-platform
• Supports reverse engineering / visualization of existing databases

Cons

• More complex than simple tools
• Best for people who really want a full modeling workflow

 

pgAdmin

After trying multiple options, I stayed with pgAdmin because it gives me what I need without extra steps:

Pros

• Very visual and easy: I can quickly understand relationships like artists → albums → tracks
• Works directly with my PostgreSQL database (no importing/exporting)
• Auto-detects data types and relationships
• Good ERD export to print/share

Cons (but acceptable for me)

Sometimes I clean things up manually after schema work:

• remove NOT VALID when it’s not needed
• add missing CHECK constraints
• rename constraint names for consistency

For me this is fine, because I like having diagram + full SQL control.

 

Conclusion

There are many free diagram tools — and some are really good.
But if you want something that is:

• free
• visual
• connected to your real PostgreSQL schema

pgAdmin is a very practical choice.