问题
How would you design your database to achieve this functionality?
Consider a scenario where we want to create a product relation (package)...
Say that we create a ProductTbl
prod_id prod_name prod_fee
1 prepaid-A 19 usd
2 prepaid-B 29 usd
3 prepaid-C 39 usd
4 internet 9 usd
5 mms 1 usd
6 email 3 usd
We want to offer a product package that provides better fees for customer.
E.g. if customer choose prepaid-A + internet + mms they will have a pkg fee by 25 usd (instead of 29 usd).
DESIGN
- A pkg with same combination should only exist once.
- A pkg can have unlimited number of products, if possible. (Normally will be 2-4).
E.g. of a pkg combination
ProdPkgTbl
ppkg_id prod_name prod_fee
1 prepaid-A 25 usd
1 mms 25 usd
1 internet 25 usd
2 internet 10 usd
2 email 10 usd
3 prepaid-C 45 usd
3 internet 45 usd
3 mms 45 usd
3 email 45 usd
This means that combination
- pkgid 1 -> prepaid-a, mms, and internet for a pkg fee of 25 usd
- pkgid 2 -> internet and email together for a fee of 10 usd
- pkgid 3 -> prepaid-c, internet, mms, email all together for 45 usd
So if a customer got prepaid-c + internet only they not get the deal for 45 usd, they will pay normal fee of 39 + 9 = 48 usd.
NOW THIS TABLES are just for demo, I would like to get your input and advice to model it in a right direction.
We will need first to select-query a customer current fee plan (based on used products/services) and after that look into the product pkg and see if pkg deal is valid for them or not.
(How to do such selection? on pkg table?) How to have a good db model for this?
Please advice with urls, hints, anything with value to push me into the right direction.
Great thanks.
回答1:
You are selling goods or services from a catalog. You can also sell combinations of the above. This is called a Marketing Package (or Bundle or Combo).
A marketing package is also sold from the catalog. It can be comprised of goods, services, or other marketing packages.
The price is really different per order. You could set a base price in the good table, a monthly price in the service table, and a base price in the marketing package table.
回答2:
I was hoping for some input regarding this but maybe the question is to "messy" to answer. :o)
My model right now is like this:
ProductTbl
prod_id prod_name prod_fee
1 prepaid-A 19 usd
2 prepaid-B 29 usd
3 prepaid-C 39 usd
4 internet 9 usd
5 mms 1 usd
6 email 3 usd
ProductPkgTbl
ppkg_id prod_id prod_name
1 1 prepaid-A
1 5 mms
1 4 internet
2 4 internet
2 6 email
3 3 prepaid-C
3 4 internet
3 5 mms
3 6 email
ProductPkgFeeTbl
ppkg_id ppkig_fee
1 25
2 10
3 45
But there are some flaws in above, and it is that someone could insert same products in different pkg and with different fees.
I really can't figure out how to be sure that a pkg is unique, with sql. Well, of course a programming language / stored procedure / triggers etc can make the check ! But I want to have a design that is 100% flawless.
Please push me in the right direction with your experience in matters like this...
来源：https://stackoverflow.com/questions/14527203/database-model-for-products-and-product-package-with-different-combinations