Question
Consider the following relations containing airline flight information: Flights (flno: integer, from: string, to: string, distance: integer, departs: time, arrives: time) Aircraft (aid: integer, aname:
Consider the following relations containing airline flight information:
Flights (flno: integer, from: string, to: string, distance: integer, departs: time, arrives: time)
Aircraft (aid: integer, aname: string, cruisingrange: integer)
Certifed (eid: integer, aid: integer)
Employees (eid: integer, ename: string, salary: integer)
Note that the Employees relation describes pilots and other kinds of employees as well; every pilot is certified for some aircraft (otherwise, he or she would not qualify as a pilot), and only pilots are certified to fly.
Write the following queries in domain relational calculus.
1. Find the eids of pilots certified for some Boeing aircraft.
2. Find the names of pilots certified for some Boeing aircraft.
3. Find the names of pilots who can operate planes with a range greater than 3,000 miles but are not certified on any Boeing aircraft.
4. Identify the flights that can be piloted by every pilot whose salary is more than $100,000.
?
Step by Step Solution
There are 3 Steps involved in it
Step: 1
Get Instant Access to Expert-Tailored Solutions
See step-by-step solutions with expert insights and AI powered tools for academic success
Step: 2
Step: 3
Ace Your Homework with AI
Get the answers you need in no time with our AI-driven, step-by-step assistance
Get Started