Afaik there is a feature/bug in current implemention of market history recording, which causes that volume of non-bts pairs trading wont be recorded to the database, as a result prices wont be recorded as well.
I will look into this issue.
Is it ok to record the volume of asset whose ID is smaller? The volumes of bts pairs are recorded this way, however it looks odd for other assets. Will the Gui be able to handle the flipping markets in this case?