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

Differentiate between primary and secondary storage, Differentiate between ...

Differentiate between Primary and secondary storage? Primary and secondary storage - Primary storage device stores the data temporarily. Primary storage is commonly used thro

Which data type can store unstructured data, Which data type can store unst...

Which data type can store unstructured data? Raw data type can store unstructured data.

Explain consistency model , Explain in detail the consistency model of the ...

Explain in detail the consistency model of the distributed file system you studied (GFS or AFS). Present the consistency model chosen and how it was achieved through design. Clarit

Computing the closure of a set of functional dependency, What is meant by c...

What is meant by computing the closure of a set of functional dependency? The closure of F denoted by F + is the set of functional dependencies logically implied by F.

Differentiate between key and superkey, Differentiate between Key and super...

Differentiate between Key and superkey? Key and superkey - A key a single attribute or a combination of two or more attributes of an entity set in which is used to identify o

What is a homogeneous distributed database, What is a homogeneous distribut...

What is a homogeneous distributed database? In homogeneous distributed databases, all sites have the same database management system software, are aware of one another, and agr

Update operations in dbms - insert operation, Update Operations and Dealing...

Update Operations and Dealing with Constraint Violations There are three basic operations to be executes on relations: Insertion Deletion Update The INSER

Why is database redesign necessary, Why is database redesign necessary? ...

Why is database redesign necessary? Database redesign is essential for two reasons. First, redesign is essential both to fix mistakes made during the initial database design. S

Foreign keys , Foreign Keys and NULL Let us take the relation:         ...

Foreign Keys and NULL Let us take the relation:                 DEPT DEPT ID DNAME BUDGET D1 M

What is inheritance, What is inheritance? Define it in detail?  Inheri...

What is inheritance? Define it in detail?  Inheritance Inheritance can be at the levels of types, or at the level of tables we first consider inheritance of types, then i

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