精选优质文档-倾情为你奉上一、 Consider the following information in an airport databasel An airport is described by its name and the city that the airport locates atl Each airplane has an unique registration number and also the date of production as its descriptive attributesl Each airplane model is identified by a model number and has a capacity and a weightl A technician is characterized by an unique technician_id, his name and his phone number l Each airport accommodates a number of airplan
