No ID associated with a Position?

When getting a list of positions, is there no ID associated with that position? If I opened 3 different positions for the same symbol on 3 different days at 3 different buy prices, what distinguishes these 3 positions with an identifier? Wouldn’t the asset_id be the same for all 3? How can I distinguish that I want a certain position out of 3 that all have the same symbol?

OR

if 3 different positions are bought against the same Symbol, does the system only maintain 1 record of position entry and the shares and other portions are all averaged in for that 1 record? Would there be then just 1 open position for a Symbol?

Thanks…