This is the number of big blinds won by the player. Take the Player stat 'BB Won' for example. If you want to make a Player stat which does calculations based on the amount won in each hand, but across all hands, then you can't use the column 'amt_chips_won', you need to make another column which uses the database field 'tourney_hand_player_statistics.amt_won'.

In a Player stat if you were to use the column 'amt_chips_won' then that would have the value across all hands. Sum(tourney_hand_player_statistics.amt_won) The Hand stat Chips Won and the Player stat Chips Won effectively do the same thing, but are defined differently because the Hand stat is just for individual hands, and the Player stat is for the total across all hands.