MySQL 查询实战：用户关联旅客信息分析

查询哪些用户添加了手机号为‘18902156699’，并且性别为‘女’的旅客。\n\nsql\nSELECT User.username, User.password, User.balance\nFROM User\nINNER JOIN Passenger ON User.username = Passenger.username\nWHERE Passenger.phone_number = '18902156699' AND Passenger.gender = '女';\n\n\n2) 查询旅客表中有多少个名为“赵六”的记录。\n\nsql\nSELECT COUNT(*) AS record_count\nFROM Passenger\nWHERE passenger_name = '赵六';\n\n\n3) 查询旅客表中的“赵六”，性别是男和女的分别有几个。\n\nsql\nSELECT gender, COUNT(*) AS count\nFROM Passenger\nWHERE passenger_name = '赵六'\nGROUP BY gender;\n\n\n4) 查询每个账号所关联的旅客，分别有多少个手机尾号为8的，并按照数量从高到低进行排序。\n\nsql\nSELECT User.username, COUNT(*) AS count\nFROM User\nINNER JOIN Passenger ON User.username = Passenger.username\nWHERE RIGHT(Passenger.phone_number, 1) = '8'\nGROUP BY User.username\nORDER BY count DESC;\n