Representing Bikes
To keep track of the Bikes you have on hand, what you have ordered and what you have sold you need an accurate way to represent a Bike in a notebook, spreadsheet or database.
The main you attributes of an individual Bike are:
- Type: Urban, BMX, ATB...
- Brand
- Model Name
- Internal Stock Number
- Manufacturer's Stock Number
- Color
- Size
- Who: Boy's, Girl's, Men's Women's, Anybody
- Wholesale Cost
- Retail Price
- Sale Price (when "on sale")
- Actual Sale Price
- Serial Number
You might notice that the above are different classes of data. For example,
- type,
- brand
- model name
represent a particular Model, independant of color, size etc. Whereas
- stock number,
- cost,
- price,
- size,
- color,
- who
represent what I call a 'Mold' in the sense that a mold stamps out actual physical bikes. The Mold is also keeps track of stock on hand and stock ordered and backordered.
Actual physical Bikes are each defined by:
- serial number,
- notes
And once they are sold, they also have
- an associated sale,
- a sale price,
- an owner.
And as time goes on physical Bikes will acquire a
- repair history.
In a relational database (or object-oriented database) you define Model, Mold and Bike tables (or entities) and assign the relevant fields (as listed above) to each. Models, Molds and Bikes have database 'relationships' to each other. And Bikes have relationships to Sale and Owner entities.
In a spreadsheet or simple database you have to lump all the attributes together, in columns, representing a sort of Bike-Mold-Model hybrid. Even such a simplified representation is a big help to keeping track of your bikes.
