Fast Takes

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Name: John McDowall
Location: Redwood City, California, US

Wednesday, September 24, 2003

Prevayler - orthogonal Persistence..

I noticed this Slashdot | Prevayler Quietly Reaches 2.0 Alpha, Bye RDBMS? today after my previous post about data impedance. If you cut away the hype there might be something here.


Another similar solution I am playing with just now is db40 which is a Java and .Net object database. It is very elegant and easy to use.

Tuesday, September 23, 2003

Impedance mismatch in Development

In Java is the SUV of programming tools a widely quoted article by Philip Greenspun he raises the issue of complexity. While I favor Java as a programming language I think he raises a few interesting issues.


The problem is not the programming language but rather the infrastructure we have built. To create an application that takes a string as input through a web form and then stores it in persistently a developer must know a wide range of technologies. This is true no matter which particular approach they use. If I use Java it is HTML/JSP/Servlets/Java/JDBC/SQL at a minimum if I use another approach the stack is similar (HTML/PHP/CGI/Perl/DBI/SQL). The number of transformations the simple string goes through from the web page to the database is significant. The impedance mismatch comes from the need to translate amongst datatypes. If it is a real world problem with complex types the problem quickly becomes hard.


Developing applications with clean interfaces and separation of presentation layers, business logic and persistence is moving to the extreme. Some of the work on orthogonal persistence attempted to simplify the problem but it ran into its own set of issues around being too tightly coupled.


The internet is a wonderful application development platform but we are making it too complex to do useful and simple things. While XML has its own set of issues it does reduce the impedence issue if an XML datastore is used. There are still several technologies in play but one data format. (XHTML/XSLT/XML/REST/XML-Store) - are we better off?

Tuesday, September 16, 2003

Inspirational Technology -Cool stuff

A few people have been commenting on Inspirational Technology (Sam Ruby and Jon Udell). The really cool aspect for me is that it is pointing the path to a truly distributed environment where persistence is in the background not the foreground of development.


Much of the work around orthogonal persistence in Java has stalled around synchronization of state between communicating applications. The middle ground that Kimbro takes shows the path forward to build a whole new set of collaborative applications that have persistence in the background.


I feel inspired to try and expand on the work of Kimbro and create some new services that allow data to flow with transparent persistence

Monday, September 15, 2003

Jeremy Zawodny's blog: RSS Auto-Discovery 2.0

Anything that makes it easier to connect blogs is a good thing. Therefore by definition RSS Auto-Discovery 2.0 is a good thing. The value of blogs apart from being fun; is connecting with others either in a machine or human readable fashion. Blogs are a major enhancement to the web in terms of structured relationships.


To keep blogs moving forward and creating more value through we need to keep the right balance between simplicity and power - weighted more to simplicity.