Дистанционный практикум по программированию

How to send SQL queries for check.
You must name all computed columns. Example: select min(price) as minpr from km_prices

Database schema:

 

 

1. km_prices (prices of 1 km)

class(classes of buses)

price (price of 1 km for this class)

 

2. models (models of buses) 

cod_model (code, surrogate key)

name_model (name of model)

places (number of places in a bus of this model)

            class (class of comfort)

 

3. buses (buses)

            cod_bus (code of bus)

            bus_number (registration number)

            cod_model (model of bus, foreign key)

 

4. points (stations)

            cod_point (code, surrogate key)

            name_point (name of station)

            distance (distance from starting point)

 

5. routes (routes of buses)

            cod_route (code, surrogate key)

            name_route (name of route)

 

6. points_routes (relationship between stations (points) and routes)

            cod_point (code of point, foregin key)

   cod_route (code of route, foreign key)

 

7. trips (trips of buses)

   cod_trip (code of trip, surrogate key)

   week_day (day of week)

   hour (hours of departure)

   minute (minutes of departure)

   cod_route (code of route, foreign key)

   cod_bus (code of bus, foreign key)

   tickets (number of sold tickets)