I'm not sure if I'm explaining this correctly but I'll give it a shot.
I'm trying to use Data Loader to insert CSVs of data into a Partial Pro sandbox, but I want these inserted records to use the same id18s as my Production Org, similar to what happens when a Full sandbox is refreshed.
The purpose of this is to provide a 3rd party with as near to a Production Org environment as possible, with access to the Full sandbox not being an option.
Why this is necessary is because several junction objects exist that I will need to use parent-insert/child-insert/junction-insert/rinserepeat insert operations in order to provide them with some useful test data. My concern is that I don't know of a way to easily insert junction object relationships without - after each insert step above - doing an extraction of the IDs created during the insert, doing an extensive VLOOKUP to match them with their former IDs from Production, and constructing a legend that will then need to be used to replicate the junction object records.
Is there a better way to do this? Hopefully this was clear? Available for questions and thanks in advance!