The framework is based on Model-View-Controller [MVC] architecture. While view and controller classes are a necessary part of development under CodeIgniter, Models are entirely optional. But to stick with MVC normally all database interactions are done with a Model. Here is new and simple CodeIgniter 1.7.2 Quick Reference Cheatsheet created by CodeIgniter.com .
This cheat sheet attempts to better align with the new documentation structure CodeIgniter is now using and clearly marks all new and updated functions for CodeIgniter 1.7.2 . it come with 2 version of Cheat sheets. Both of them available in easy-to-print format in A4 size paper.