Freebase -- Wikipedia for structured data?

We have discussed varying degrees of data structure on the Internet, ranging from free-text pages like Wikipedia to rigidly structured relational databases.

Freebase is like a structured Wikipedia, combining the advantages of free text and relational databases. Like Wikipedia, Freebase is open -- any user can create and change content. Unlike Wikipedia, Freebase data is structured so users can query it as they would a relational database.

This example illustrates Freebase. "Topics" are instances of formally defined "types." Here the type is person, and persons have formally defined properties like height, weight, and place of birth.

I am adding a new person (a new topic) to Freebase, myself. I was born in Pasadena, California, and when I began typing a value for place of birth, the system quickly showed the "Pasadenas" in its database with their structured descriptions. It knew that the value of the property had to be a location, and immediately displayed names and property values of locations named "Pasadena." This mechanism both saves time and assures that users have a common vocabulary.

Any Freebase user can create a new topic or change the property values of existing topic. For example, you could add yourself (a new person) to Freebase, and you could also change my place of birth from Pasadena, California to Santiago, Chile.

Thus far, Freebase sounds like a fancy relational database. However, qualified users can also change the structure itself. If one is qualified to be a "type administrator," he or she can create new types and modify the definitions of existing types. For example, one could add the property eye color to the definition of a person.

The developers of Freebase hope that, like Wikipedia, it will attract many users, some of whom are motivated to become type administrators. That way, both the content and structure of a domain of knowledge will evolve over time.

If this sounds interesting, listen to this wide ranging interveiw on Freebase and Metaweb, the system used to create it.

Using Zoho's cool form-creation service

We illustrated a three-tier application using a simple class roster file. It took me a day to develop, debug and document that application using Active Server Pages (ASP). It consists of six ASP pages, and I needed some knowledge of ASP, Visual Basic, and SQL to develop it.

I implemented the class roster application using the form-creation service at Zoho.com. It took me less than an hour to learn to use the service and implement the application. I needed no knowledge of programming -- it was similar to building the application using a simple database management system like Microsoft Access. Note also that the service-based application has powerful features like data export, access control and report sorting that are missing in the bare-bones ASP version.

The advantages of using a service to create this application are abundantly clear, but there are still questions. Will it scale -- how would it perform if we had an application with thousands of records and dozens of forms and views? Will Zoho continue offering this service -- can I count on it as part of my course curriculum? What will they charge for large databases? Would they be better off implementing their service using a file service like Amazon S3?