| 1 | SIMPLE | stats_player | index_merge | idx-stats_player-stats_layer,idx-stats_player-player_id,idx-stats_player-team_id,idx-stats_player-season_id | idx-stats_player-player_id,idx-stats_player-team_id | 4,4 | NULL | 1 | Using intersect(idx-stats_player-player_id,idx-stats_player-team_id); Using where |