Flatten JSON to a hierarchical EAV table, explore, edit, and convert back to JSON!

[Jon_Dallas]

Hey Coda!

Just built a system that lets you flatten ANY JSON into a hierarchical EAV table and then convert it back to JSON after editing - all within Coda! Check out the demo video

Why I built this

Working with complex JSON in Coda has always been challenging. If you’re working with:

• API responses
• LLM outputs/inputs (my primary use case)
• Configuration files
• Complex data structures

You know the pain of navigating nested JSON structures. You either have to flatten everything into CSV-like tables (losing the hierarchy) or work with JSON as raw text.

How it works

1. Import: Paste any JSON into the input area and click “Flatten to EAV”
2. Explore: The JSON gets transformed into a EAV table where:

• Each key becomes a node/row
• Parent-child relationships are preserved
• Values are stored and editable
• All relationships (ancestors, descendants, siblings) are tracked

3. Navigate: Use the Miller Columns view (like Mac Finder’s column view) to click through the hierarchy
4. Edit: Update any values directly in the table
5. Export: Click “Reconstruct JSON” to convert your EAV back to properly formatted JSON

Here’s what makes this special:

• Full hierarchy preservation - even deeply nested structures
• Edit any value and see changes reflected in the final JSON
• Visualize complex structures with Miller columns
• No depth limits to the hierarchy

Technical Notes

• The system converts arrays to objects with [n] notation as parents. This keeps the original order while making everything consistently navigable.
• Since it’s built on Coda tables, there are no practical size limitations beyond Coda’s standard constraints.

Get the doc

You can duplicate this document and start using it right away:

Use cases

I’m currently using this to:

• Debug complex API responses
• Create structured prompts for LLMs
• Store and edit hierarchical data that needs to be accessed by both humans and AI

Would love to hear how YOU might use this!

Happy coding!
Jon

[Rickard_Abraham]

Well done!
This will be very useful to explore json responses, thank you

[Jannis]

Great work, thanks for sharing

[Paul_Danyliuk]

Nice work!

Personally I would either use some robust JSON tree viewer app (for trees over 10-ish kilobytes or complex hierarchies) or a text editor like Notepad++ or VS Code for anything simple I can imagine it takes quite some time to ‘unfold’ that tree in Coda (creating all those rows and stuff — even in your edited loom it takes a while) so for me it’s not super practical. But it’s a great exercise and a novelty doc for sure!

Make it compile schemas for objects of different types though — maybe even some TS code or Schemas for Coda Packs — and now we’re talking

[Jon_Dallas]

Yes, agreed @Paul_Danyliuk! I don’t think the real application of this is exploring/editing nodes in JSON.

For me, the real usecase is being able to update my database with an LLM responding in JSON.

TS/schemas is a good rec! I’ll see what I can do

[Jono_Bouwmeester]

This is really excellent work, @Jon_Dallas. Useful tool, and the doc itself is beautifully built. Well done!