there scenario is here :
-Client will have contract with the company (who belongs this system).
-Client have a START_DATE & END_DATE for the project (period)
-The contract period will be count in monthly NOT year; example a contract period is 2 years=counted as 24 months.
-Client have two method to pay the contract; Whether MONTHLY or QUARTERLY
System will:
** Calculate the contract period in month.A month equal with 30 days.
- Once the admin insert the percentage of payment paid by client, system will display the percentage and amount left.
-For MONTHLY payment method the formula is (CONTRACT_PERIOD/CONTRACT_AMOUNT)
Which will show how much the client should pay per-month
-For QUARTERLY payment method the formula is [(CONTRACT_PERIOD/CONTRACT_AMOUNT)*3] which will show how much the client should pay per-quarterly
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***the main problem now is HOW TO WRITE THE CODE & FORMULA to make the system calculate the days /years in period to month?(convert) like example : "contract of client XYZ started from 1 Jan. 2008 and end on 12 march. 2009" which is equal to 406 days (forgive me if i'm wrong)or 13.5 months.
(Admin will insert the start_date & end_date= I use Date Time Picker in VB.Net.)
***How to make the system calculate the remain balance of unpaid payment : example XYZ have a contract which costed $500k and already paid 20% (the percentage will be insert by Admin; ouh.. this is another problem, when admin will put the percentage OR exact amount already paid=example XYZ already paid $50k, how many percent left?)>> System should automatically shows the amount in $
**should i write the formula/arithmetic inside the VB code or should i write in the SQL query or BOTH? and how is the formula and syntax should i use? please help me.. and if possible could anyone write a little program/codes in here...

for ur information i already finished the design of all forms and database's table (but without data and any formula)..so i just need to know what arithmetic and code should use and where is the line in VB and SQL.
sorry coz i wrote to much things in here but i have to explain it deeply so everyone will understand my problems/questions


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This post has been edited by yukirou: 05 April 2010 - 07:05 PM