Write the queries in relational algebra, Database Management System

Assignment Help:

Problem:

You are given the following schema

1. Flights(flno, from, to, distance)
2. Aircraft(aid, flno, aname, cruisingRange)
3. Certified(eid, aid)
4. Employees(eid, ename, salary)

‘CruisingRange' is the distance that can be covered by an aircraft in a non-stop mode.

(i) Write the following queries in Relational Algebra.

(a) Find the names of pilots certified for 'Boeing 747' aircraft.

(b) Find the ids of all aircraft that can be used on non-stop flights from New York to Los Angeles.

(c) Find the names of pilots who can operate planes with a range greater than 3000 miles, but are not certified on 'Boeing 747' aircraft.

(ii) Write the following queries in SQL.

(a) Find the ids of employees who are not certified at all.

(b) Find the ids of all aircraft that can be used on non-stop flights from New York to Los Angeles.

Related Discussions:- Write the queries in relational algebra

What is object oriented model, What is Object Oriented model? This mod...

What is Object Oriented model? This model is based on collection of objects. An object has values stored in instance variables with in the object. An object also having bodies

Differance between unordered and ordered file, Differance between Unordered...

Differance between Unordered and ordered file ? Unordered file do no has any sequence although ordered file has arranged in a few sequence and data are assigned in ordered form

Differentiate between horizontal and mixed partitioning, Question: In r...

Question: In relation to distributed database answer the following questions: (i) Give a brief definition of distributed database. Support your answer with an appropriate di

Determine the strong and weak entity, Determine the Strong and Weak Entity ...

Determine the Strong and Weak Entity Based on the method of foreign key, there might be arise a situation when we have to relate an entity having a primary key of its own and a

Security-drawbacks of data distribution, Security: In a centralised system...

Security: In a centralised system, access to the data can be simply controlled. Though, in a distributed DBMS not only does access to replicated data have to be controlled in many

For known, What are the function of DBA?

What are the function of DBA?

Structure of client server systems, Structure of Client Server Systems: In ...

Structure of Client Server Systems: In client/server architecture, clients show users who require services while servers give services. Both client and server are a combination of

Storage of database on hard disks, Storage Of Database On Hard Disks At...

Storage Of Database On Hard Disks At this point, it is worthwhile to note the difference among the terms file Organisation and the access method. A file organisation shows to t

What is known as heap file organization, What is known as heap file organiz...

What is known as heap file organization? In the heap file organization, any record can be placed anywhere in the file where there is space for the record. There is no ordering

How does the two phase protocol ensure serializability, How does the two ph...

How does the two phase protocol ensure serializability in database schedules? Ans: A transaction is termed to follow the two-phase locking protocol if all locking operations

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages