Kellogg Associates

Observers in Rails 1.2

Posted by Gregg Kellogg Sat, 27 Jan 2007 03:13:00 GMT

Thanks to Rick Olson for providing assistance with the proper syntax for instantiating observers in Rails 1.2. The old way was to add an observer statement to the appropriate controler, such as:

observer :user_observer

Hidden in the ignored parts of conf/environment.rb was the proper notation:

# Activate observers that should always be running
# config.active_record.observers = :cacher, :garbage_collector

This makes the last of my deprecation messages go away!

Gregg

Posted in Ruby on Rails | no comments | no trackbacks

Eager Finder SQL

Posted by Gregg Kellogg Mon, 06 Nov 2006 01:31:00 GMT

EagerFinderSql allows custom SQL to be specified when doing eager loading of associations through the :include option to find. This allows for purpose-constructed queries to be used and still result in a fully linked object model.

Background

ActiveRecord constructs SQL to satisfy the requirements of a find request. Associations allow for customized SQL to be specified, using the :finder_sql option, but this has not been available when performing eager loading using the :include option. The result is that a standardized query is constructed to bring in the associated tables using LEFT OUTER JOIN. For some queries, this can be result in expensive queries and potentially very large result sets.

Custom SQL

EagerFinderSql addresses this problem by allowing :finder_sql to be added to find options when the :include option is also specified.

Project Communication

Posted by Gregg Kellogg Thu, 02 Nov 2006 18:00:00 GMT

Many software projects fail to deliver on-time and on-budget and a factor in that is normally inefficient project communication. Studies have shown that software teams that consistently deliver on-time and on-budget communicate in an effective manner. These teams stay in contact constantly, but wisely use each other’s time during the communication process and are careful not to waste other people’s time.

Below are some tips for enhancing project communication when working in software development projects:

Posted in Design | Tags Scrum | no comments | no trackbacks

Thoughts on Extreme Programming

Posted by Gregg Kellogg Thu, 02 Nov 2006 18:00:00 GMT

A popular trend in systems development circles is the so-called Extreme Programming Paradigm. XP has proven to be quite effective at rapidly producing system functionality, and it includes many practices that should be considered by any development team (e.g., Test Driven Development or TDD). However, there are many pitfalls to XP that don’t necessarily make it the best technique for many organizations.

Posted in Design | no comments | no trackbacks

Web Design Goals

Posted by Gregg Kellogg Thu, 02 Nov 2006 18:00:00 GMT

Working with legacy software systems provides its own considerations, but there are some general goals that can be stated for web-based software applications. To the degree that the nature of system upgrades substantially touches these areas of system design, it is important to consider the following goals within the system design. Well designed applications should meet the following goals in order to provide lasting value:

Posted in Design | no comments | no trackbacks