I am a bit confused and wish to share this with you for help. We are designing a billing application to bill telephone calls. It currently handles a single rate plan. So what it does is that it looks up the RATES table and matches the called number area code with the RATES.ACCESS_Code field to find the tariff for that area and multiplies that by the number of minutes. Here is the current schema.
• ID (pkid)
• Called Number
• Destination Name
• Access_Code (pkid)
Now the problem is that we need to process calls based on RATES per OPERATOR. Each operator is a telephony carrier with similar RATES. However, each call will be prefixed with a number to indicate which operator carried that call. Accordingly, the database should relate that prefix with the proper operator and then looks up the RATES that are related to that operator.
In conclusion we will have a replica of the RATES table for multiple operators. An operator is only supposed to have two fields I guess (name and ID).
So now we need to re-engineer the schema to adapt to this situation.
Eg. 95004433313445 (Will be identified as BT operator)
93004422376234 (Will be identified as AT&T operator)
Can anyone help please?