Define Product Class

[nicole08]

Hi,

I have this Product class which is related to several other classes, e.g. Category, Designer, etc. In database, I have column CategoryID, DesignerID. When defining a Product class, shall I have Integer property for CategoryID, DesignerID? Or, shall Ihave String property for CategoryName, and DesignerName?

Solution 1: Integer Property
When I display a product, I'll initialize a Product class, get the CategoryID and DesignerID, and then initialize Category class and Designer class, to get the Category name and Designer name to display. That means I will access database 3 times.

Solution 2: String Property
When I display a product , I'll initialize a Product class, use a JOIN SQL statement, and set Category name and Designer name directly.

So, which is the proper solution? I think Solution 1 is the correct one. But what can I do to eliminate 3-time database accessing?

Thanks,
Nicole

 

[DonQuichote]

What I do in such a case is to provide the IDs to the object, even if only internally. This allows me to do a lazy fetch of the related records. In my case, a Product instance would have both a CategoryID property and an (often lazy) getCategory method.

My code is usually structured as follows: I have a "backend" object that has persistent collections ("table wrappers"). These collections provide the persistent objects ("record wrappers").
This can impose a problem: each Product instance has to know both the Categories collection and the Designers collection to make the lazy getters work. What I do in such a case is to pass the Backend object around, which provides all the collections the object needs.