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

Assignment Help:

Consider the following relational schema:
Doctor(DName,Reg_no)
Patient(Pname, Disease)
Assigned_To (Pname,Dname)
Give expression in both Tuple calculus and Domain calculus for every of the queries:
(i) Get the names of patients who are assigned to more than one doctor.
(ii) Get the names of doctors who are treating patients with ‘Polio'.

Ans:
(i)Tuple Calculus:
{p[PName] | p ∈ PATIENT ∧ ∃a1, a2 (a1 ∈ ASSIGNED_TO ∧ a2 ∈ ASSIGNED_TO ∧
p[PName] = a1[PName] ∧ a1[PName] = a2[PName] ∧ a1[DName] ≠ a2[DName])}
Domain Calculus:
{p | ∃p1, d1, p2, d2 ( ∈ PATIENT ∧ ∈ ASSIGNED_TO ∧
ASSIGNED_TO ∧ p1 = p2 ∧ d1 ≠ d2)}
(ii)Tuple Calculus:
{u[Dname] | u ∈ ASSIGNED_TO ∧ ∃t (t ∈ PATIENT ∧ t[Disease] = ‘Polio' ∧
t[PName] = u[PName])}
Domain Calculus:
{d | ∃p1, p2, s2 ( ∈ ASSIGNED_TO ∧ ∈ PATIENT
∧ p1 = p2 ∧ s2 = ‘Polio')}

#### Er schema, Consider entity type Employee with attributes empNumber (this is...

Consider entity type Employee with attributes empNumber (this is unique), empName, and the year when he/she was hired. An employee can either be a technical employee, a marketing e

#### Copy data from one database to another database, Copy Data from One Databas...

Copy Data from One Database to another Database Project Description: I am having two MySQL databases with same tables. I just need to copy one Data from one to another dat

#### The transactions, The Transactions- A transaction is definite as the unit o...

The Transactions- A transaction is definite as the unit of work in a database system. Database systems that deal with a huge number of transactions are also termed as transaction p

Define deadlock avoidance. An alternative method for avoiding deadlocks is to needs additional information about how resources are to be requested. Each request requires the s

#### Case-based online phone repair, please i request for your assistance in de...

please i request for your assistance in developing a case-based online phone repair

#### Sql, Events4Fun is an event management company in Europe with branches in S...

Events4Fun is an event management company in Europe with branches in South America as well. The company is well-known for its efficiency, good-quality services, and affordable char

#### Determine the types of methods for retrieving rows in python, Describe the ...

Describe the two types of methods for retrieving rows in Python? Fetchone()- Returns the next row as a sequence Fetch all()- Returns the entire result set like a strin

#### Employee elation with information, Consider a database application that dea...

Consider a database application that deals with an Employee relation with information such as SIN, name, data of birth (DOB), and DID (the ID of the department at which the employe

#### What is data model, A Data Model in software engineering is an abstract...

A Data Model in software engineering is an abstract model that organizes and documents the business data for interaction between team members and is used as a plan for creating

#### Abap/4 program, It is not possible to make an ABAP/4 program, which having ...

It is not possible to make an ABAP/4 program, which having only Subroutines. False. We can make ABAP/4 program, which having only Subroutines.