When you include multiple rates and rooms in a ‘Create promotion’ request, we will create
promotions for all valid combinations of rates and rooms.
For example, if the following rooms and rates are sent via the ‘Create promotion’ request:
The promotions API will create promotions for all possible combinations of ‘room id’ and ‘parent_rate_id’ included in the request.
In this example, if the only valid room and rate combinations are between room id 1423432 and parent_rate id 756878 on one hand, and room id 325436 and parent_rate id 543754 on the other, then promotions will be created for these two valid room id/parent_rate id combinations.