Give expression in tuple calculus and domain calculus, Database Management System

Assignment Help:

Consider the subsequent relation schemes:

 Project (Project#, Project_name, chief_architect)

 Employee (Emp#, Empname)

 Assigned_To (Project#, Emp#)

 Give expression in Tuple calculus and Domain calculus for each of the queries below:

 (i) Get the employee numbers of employees who work on all projects.

 (ii) Get the employee numbers of employees who do not work on the COMP123 project.

 Ans:   (i) Tuple Calculus:

 {t[Emp#] | t ∈ ASSIGNED_TO ∧ ∀p (p ∈ PROJECT ∃u (u ∈ ASSIGNED_TO ∧ p[Project#] = u[Project#] ∧ t[Emp#] = u[Emp#]))}

 Domain Calculus:

 {e | ∃p ( ∈ ASSIGNED_TO ∧ ∀p1 ( ∈ PROJECT   ∈ ASSIGNED_TO))}

(ii) Tuple Calculus:

{t[Emp#] | t ∈ ASSIGNED_TO ∧ ¬∃u (u ∈ ASSIGNED_TO  ∧ u[Project#] = 'COMP123'∧ t[Emp#] = u[Emp#])}

 Domain Calculus:

 {e | ∃p ( ∈ ASSIGNED_TO ∧ ∀p1, e1 ( ∉ ASSIGNED_TO  ∨ p1 ≠ 'COMP123' ∨ e1 ≠ e))}


Related Discussions:- Give expression in tuple calculus and domain calculus

Define tuple variable, Define tuple variable Tuple variable is a type o...

Define tuple variable Tuple variable is a type of variable whose domain is the set of all tuples.

EER models, Ask question #MinimThe Georgia Tech Library (GTL) has approxima...

Ask question #MinimThe Georgia Tech Library (GTL) has approximately 16,000 members, 100,000 titles, and 250,000 volumes (an average of 2.5 copies per book). About 10 percent of the

Write a short note on participation role, write a short note on participati...

write a short note on participation role? Participation role: roles are indicating in E-R diagram by labelling the lines that connect diamonds to rectangles.

Distributed and client server databases, Distributed And Client Server Data...

Distributed And Client Server Databases Introduction This unit tells the distributed database systems which are primarily relational and one important execution model: the

Define the immediate update, Define the Immediate Update The immediate...

Define the Immediate Update The immediate update methods may apply changes to the database on disk before the transaction arrives a successful conclusion. Though, these change

What is meant by mean time to failure, What is meant by mean time to failur...

What is meant by mean time to failure? The mean time to failure is the amount of time that the system could run continuously without failure.

What is the role of order by clause, What is the role of ORDER By Clause? ...

What is the role of ORDER By Clause? ORDER BY clause: The ORDER BY clause permits you to sort the records in your result set. The ORDER BY clause can just be used in select s

Database, . Ashutosh Dubey who is the director of Gyan Gurukul want a three...

. Ashutosh Dubey who is the director of Gyan Gurukul want a three-level schema architecture for the Gyan Gurukul Company that provide better security also design a data abstraction

Distributed Database query processing , I am doing research in this area, e...

I am doing research in this area, especially in sime join and join efficacy when several relations have been queried. Relations located in different sites. I need something like n

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd