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

Explain retrieval in qbe, Explain retrieval in QBE? Retrieval in QBE : ...

Explain retrieval in QBE? Retrieval in QBE : A "GUI" for expressing queries. Based on the Domain Relational Calculus (DRC) Actually invented before GUIs. Very co

Inconsistent analysis-problems of concurrent transactions, Inconsistent Ana...

Inconsistent Analysis : The problem as given with transactions T1 and T2 where two transactions interleave to make incorrect result during an analysis by Audit is the instance of s

Give the limitations of sql authorization, Give the limitations of SQL auth...

Give the limitations of SQL authorization. The code for checking authorization becomes intermixed with the rest of the application code. Implementing authorization by applic

Explain mechanism of nested queries, Explain mechanism of nested queries? ...

Explain mechanism of nested queries? SQL gives a mechanism for nesting subqueries. A subquery is a select from where expression that is nested within one more query. A common u

Sequences-data control, Sequences Sequences: Automatically produ...

Sequences Sequences: Automatically produce unique numbers Are sharable Are typically used to make a primary key value Replace application code Speed up t

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

Explain nested relations, Explain nested relations? Nested relations ...

Explain nested relations? Nested relations The assumption of INF is a natural one in the bank examples we have considered. However, not all applications are best modelled

Describe deductive databases and relational databases, Problem : (b) A ...

Problem : (b) A deductive database system is essentially the outcome of applying mathematics logic to database management, where logic is used for both data representation and

Icloud based storage, Advantages and disadvantages of icloud based storage

Advantages and disadvantages of icloud based storage

What are the two integrity rules, What are the two integrity rules? An...

What are the two integrity rules? Ans: The two integrity rules are: Entity Integrity Rule & Referential Integrity Rule. Entity Integrity Rule - If the attribute A of rel

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages