Percentage Discount

[Henry]

Hello,
I got a problem when I try to get the info from sells with discounts on Prestashop (V. 1.6.1.17); This is the situation, on my company we are using Prestashop to sell On-Line, perhaps for all the bak we are getting the info from the orders and processing it on another system (one made inside the company).

On the beginning of the implementation, we think that we only were going to use the value discounts, but now we have the necessity to make marketing campains, that must use percent discounts, therefor the rutine to obtain the info from the orders on Prestashop must be changed.

The principal differences we found on this new kind of discounts was:

1.- on table ps_order_detail, field reduction_amount, reduction_amount_tax_incl y reduction_amount_tax_excl , are getting the value of 0.

2.- on table ps_order_detail, field reduction_percent, are getting the percentaje that apply to the product.

3.- on table ps_orders, fields total_discounts, total_discounts_tax_incl y total_discounts_tax_ecl, aren't getting the value when the product just have the percent discount.

Thats why I want to ask you the next:
* When I use only the percent discount, fields that show the reduction (on table ps_order_detail) and discounts (on table ps_orders), always show 0 ?
* If yes, the total value of discount that on the other process was calculated on the fields total_discounts, always is necesary to get it from the detail (getting it from price * quantity * percentage)?
* When we use the both kind of discounts (value and percetage) on the same product, on an order, this info is saved on diferents fields?, I mean the percetage just is saved on the field reduction_percent and the value of discount on field reduction_amount and total_discount?; In other words, to obtain the total discount that apply to this product, I must add the value on the fields reduction_amount plus what I get from the percentage?

Thank you in advance for your support.
Greetings.

Edited July 13, 2018 by Henry (see edit history)