Table: train_services
Columns: no
origin_city_country
destination_city_country
train_name_no
operator_name
distance
no_of_stops
frequency
scheduled_running_time

Question: What is the operator name when the distance is 3105km?
SQL: SELECT "operator_name" FROM train_services WHERE "distance" = '3105km'

Question: What is the distance for the train nameno is hapa sup express /12997?
SQL: SELECT "distance" FROM train_services WHERE "train_name_no" = 'Hapa sup Express /12997'

Question: what is the no when the distance is 4168km?
SQL: SELECT "no" FROM train_services WHERE "distance" = '4168km'