Mark’s Site

If there’s one thing I’ve learned about application development, it’s to not get overly excited. Over excitement in my case often leads to errors, both small and large, probably because i just rush ahead without proper planning. The first thing you HAVE to do when designing systems is sit down and just think about all the things your system will have and do. Sit and don’t even THINK about coding or how to code anything yet. Just have a high level view of your system and begin to think about the relationships between data.

For example, will your system have both pages and page categories? Will the page categories have parent/child relationships with itself to form a pretty tree of all your data? What fields will you want for all of these different parts of the system?

Real world example

At this stage in the process, you need to nut out the basic objects of your system.

For my CMS, I came up with a list of objects that I wanted my system to include, grouped into broad categories that I will later call ‘modules’:

• Members
• Person
• Member (authenticated Person who has access to system)
• Member Session (for tracking logins (time and ip addresses of login)
• Security
• Role (admin, staff, etc)
• Permissions (view, add, delete, etc)
• Policy Areas (areas of the system I wish to secure with the security system)
• Documents
• Document
• Document Category (to provide structure for documents)
• Pages
• Page
• Page Category (to provide structure for pages)
• Menu Item (to provide structure for page categories)
• Page Document Relation (to allow multiple documents to a given page)
• Page Rating (to allow ratings for pages)
• Page Comment (to allow comments for a given page)

When you have this general idea, it’s time to move onto an ER (Entity Relationship) diagram, where the fun of application planning and development really starts (well it’s my favourite part anyway).