Consider relational schema and construct algebra query, Database Management System

Assignment Help:

Consider the following relational schema:
PERSON (SS#, NAME, ADDRESS)
CAR (REGISTRATION_NUMBER, YEAR, MODEL)
ACCIDENT (DATE, DRIVER, CAR_REG_NO)
OWNS (SS#, LICENSE)

Construct the subsequent relational algebra queries:
(i) Find out the names of persons who are included in an accident.
(ii) Find out the registration number of cars that were not involved in any accident.
Ans: (i) πNAME(PERSON) ∩ πDRIVER(ACCIDENT)
(ii) πREGISTRATION_NUMBER(CAR) - πCAR_REG_NO(ACCIDENT)

Related Discussions:- Consider relational schema and construct algebra query

What are stand-alone procedures, What are stand-alone procedures? Proce...

What are stand-alone procedures? Procedures that are not part of a package are called as stand-alone because they independently defined. A good example of a stand-alone procedu

Special comparison operator used in where clause-dml, Special comparison op...

Special comparison operator used in where Clause a. between. ...and...It gives range among two values (inclusive) Example: SELECT ENAME, SAL FROM EMP WHERE SAL BETWE

Function module, When a function module is activated syntax checking is per...

When a function module is activated syntax checking is performed automatically. YEs, a function module is activated syntax checking.

What are the authentication modes in sql server, What are the authenticatio...

What are the authentication modes in SQL Server? How can it be changed? Windows mode and Mixed Mode - SQL and Windows. To alter authentication mode in SQL Server click Start, P

Define signal, Define Signal. It allows methods to respond to events tr...

Define Signal. It allows methods to respond to events triggered by themselves or by other processes. Each signal corresponds to an exacting event. A signal is represented in Sy

Define the five basic operators of relational algebra, Define the five basi...

Define the five basic operators of relational algebra? Five basic operators of relational algebra are: 1. Union (∪∪∪∪) - Selects tuples which are in either P or Q or in both

ERD, entity relationship diagram about finance

entity relationship diagram about finance

#normalisation.., define normalisation and functional dependency

define normalisation and functional dependency

Find out the names and company names from database, Find out the names and ...

Find out the names and company names of all employees sorted in ascending order of company name and descending order of employee names of by which company. SELECT EMPLOYEE_NAME,

Database manager, Database Manager It is the interface among low-leve...

Database Manager It is the interface among low-level data, queries and application programs. Databases typically need a large amount of storage space. It is kept on disks, as

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages