Knowledge Network Graph Visualization

From time to time I received requests for MindMap or ConceptMap like graph visualization (nodes and edges style) in Piggydb or Oinker. But I thought there were things to consider in order to implement it since the models in both applications were document-oriented as I explained in an Oinker Blog entry.

Recently I came up with an idea and implemented it in Oinker as below:

The problem of displaying document-oriented data in a graph view is that a document tends to contain many large nodes which are not suitable for bird’s eye overview. So we should deal with these nodes somehow to avoid the verbosity of being precise. The idea I came up with is a way to select nodes for a graph. I call these selected nodes “topic nodes“.

Currently a topic node is:

  • a node whose content has only one word or sentence.
  • a node whose content length is shorter than or equal to 30.
  • a node whose content is not Markdown
  • a node whose content is not a URL
  • a node whose content is not a file

You can check out an example of how topic nodes work in Oinker’s graph view at:

This feature is still experimental and waiting for your feedback.

Oinker –

Piggydb and Oinker as a Content Publishing Platform

Hi there,

It’s been a while. These days I’m working on a web service “Oinker” off and on, squeezing time from busy days.

Recently, I’ve started pulling well-proven features from Piggydb and adding them to Oinker. One of them is a content publishing capability which is implemented as “Anonymous Access” in Piggydb (sample site).

Oinker’s publishing feature is more sophisticated than Piggydb. You can publish your content on a room basis. A room is like a chatroom in Oinker and it has a chat timeline and a board on which you create content with your roommates.

A room is composed of a timeline and a board

You can make a board open to public so that anonymous visitors can view the content, and additionally allow logged-in users who are non-members of the room to view the timeline and post messages to it. So you can not only publish your content, but also collect feedback from audience.


What kind of content can you create in Oinker? Just check out the sample content: Unknown Tokyo


Oinker is now open beta!

You can sign up for free at:

I’m looking forward to your feedback ;-)

What is Oinker?

I’ve launched a blog to deliver weekly updates on Oinker:

Oinker is now accepting invitation requests!

Happy new year 2015 from Japan! I hope you have a wonderful year, especially in terms of knowledge work :-)

As this year begins, the newborn service Oinker starts accepting invitation requests.

As you saw in the movie, Oinker is extremely simple. You just chat alone or with your friends and connect the comments (oinks) by dragging and dropping.

That’s all, but its potential is enormous.

I’ve been using it in real business projects with my colleagues for about a year, mainly for ideation, task and knowledge management, and it’s been just amazing. I’ll write the details of these use cases at the Oinker blog.

The best way to feel the potential is to experience it yourself, so if you are interested in trying it out, please email to

Oinker beta-test is about to start!

Finally, this day has come.

As I wrote in last week’s blog post, I’m going to send invitations of Oinker beta-test to the Piggydb Supporters after this post published.

What is Oinker? Just look at the video below:

If you are interested in trying it out, but not a Piggydb Supporter, please consider to buy the Piggydb Supporters Edition or wait for the next phase of inviting beta testers on request basis, which will start in the first quarter of the next year.

You can also get the updates of the service via Twitter:

A whole new web service ‘Oinker’ coming soon!

Hi there,

It’s been another break in developing Piggydb for almost a year. It was probably the longest but I believe the most important pause ever in this project.

I’ve been working on a new web service that shares many concepts with Piggydb, and finally, it’s about to enter the phase of inviting beta testers.

I’m going to start with invitations for Piggydb Supporters to join the first group of beta testers.

Stay tuned!



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