Why your Customer or Item Number should not have a built in meaning

Recently I was involved in some data maintenance for an organisation where a combination of alpha and numeric characters were used in the Item Code. The intention was to try and describe the item using a ’logical’ contraction of the item description. This perpetuated an age old practice in the organisation concerned, a practice that is redundant when using today’s computerised systems.

Another variation I have run into is Customer numbers starting with N or 2 for NSW and V or 3 for Victoria

The quickest way to key a Customer or Item number is to use the numeric key pad.

So the rules I was taught to live by are:

• Always start you numbering system with a prefix of 1 that way you don’t have to key leading zeros into an alphanumeric field.
• Assign all subsequent Customer and Item numbers on a Sequential Basis. Do not attempt to ascribe any logical construct to the number allocation process.
• Assign Items Numbers using 4 digits followed by a Check Digit Verifier (CDV). The resultant 5 digit Item Number can then be used in any standard barcode system.
• Assign Customer Numbers using 5 digits followed by a CDV that way a 6 digit Customer Number cannot be confused with a 5 digit Item Number.

I use a Modulus 10 Weight 3 CDV allocation rule as described in this Wikipedia page https://en.wikipedia.org/wiki/Check_digit.