As you know, the CDetailView widget displays details of a single model. If no formatting is specified, boolean values that are stored in the database as 0 and 1, are represented in the detail view as 0 and 1. If formatted as boolean, they are represented as 'No' and 'Yes'. We want to add i18n support, so that Yes and No appear in the current language.
Countries sometimes change their laws pertaining to timezones and daylight saving times. This means that GMT+2 can be a different time this August compared to last August! However, by using php's DateTime class (instead of timestamps), we can do both "format" and "timezone" conversions on a single DateTime object (only 2 lines of code) for date, time, timestamp and datetime types - while php takes care of nightmares such as current and historical timezones and daylight saving times.
Uploading files in a webapp can be extremely tricky and sometimes the quickest way to do it is to store the file directly in the webserver or into a DNS (like Amazon S3) and then to save the link and the metadata inside a table in the DB. The thing is that you'll have to deal with file permissions, server storage, file management and so on (which is perfectly fine, by the way).
Occasionally one wishes to set systemwide parameters for an application, such as a contact address for email, an application name, or setting an option that guides major behavior. Yii provides for setting of static parameters in the configuration file, and this article talks about how to do it conveniently.