Length and short are equal. For every short hand sold, there must be more than one hand sold. It's just an active transaction. If it is an active short, or even an empty single plus position. If it is an active purchase, it is more than one order.

Simply put, it is to take a single order into the air, so even if the empty order increases, at this time, a lot of single orders are actually consumed, but it will not be counted as an increase in positions.