Hey,
To tell you the truth I have not tried adding database support, since the marketplace does not currently support it! (No C++ code…)
But if your database supports saving actor variables (the ones that are replicated actually) then I don’t see why this will be a problem.
The things that need to be saved are: which placeholder belongs to what inventory (actually the inventory’s array list), the weights (if you use them) and from the placeholder save like 5-6 variables.