mysql - Query By Example. find passenger who have bought two same ticket -

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schema:

flight (flight_id, date, from, to)

passenger (passenger_name, gender)

ticket (ticket_id, flight_id, passenger_name, class, price)

i know how find passenger have bought more 1 ticket. don't know how find passenger have bought 2 ticket.

if want passengers have bought 2 tickets flight then:

select   passenger_name,          flight_id     ticket group passenger_name,          flight_id having   count( ticket_id ) = 2;

if want passengers have bought more 1 ticket flight then:

select   passenger_name,          flight_id     ticket group passenger_name,          flight_id having   count( ticket_id ) > 1;

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