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

Describe integrity and security, Describe integrity and security? a) ...

Describe integrity and security? a) Domain constraint b) Referential integrity A value that appears in one relation for a given set of attributes also appear fo

Create table statements for original database, MySQL statements for extendi...

MySQL statements for extending the database to incorporate new facilities Deliverables for submission You must submit the following deliverables in the Assignment Dropbox in

What are ways of finding out derived attributes, What are ways of finding o...

What are ways of finding out either an update is required or not for derived attributes? The ways to find out an update is required or, not are as: Explicit update

Define single value and multivalued attribute, Define Single Value and Mult...

Define Single Value and Multivalued attribute Single value attribute comprise a single atomic value for an entity and multivalued attribute may have much more than one value f

Illustrate different types of locks in sql server, Illustrate different typ...

Illustrate different types of Locks in SQL Server. There are three kinds of locks in SQL Server i.) Shared locks - These are used for operations which don't allow any update

Consistency error-database errors, Consistency error : These errors happen ...

Consistency error : These errors happen due to the inconsistent state of database caused may be due to wrong implementation of commands or in case of a transaction abort. To overc

What is identity, What is Identity? Identity (or AutoNumber) is a colum...

What is Identity? Identity (or AutoNumber) is a column that automatically produces numeric values. A start and increment value can be set, but most DBA leave these at 1. A GUID

Explain sorted file with advantages, Explain sorted File with advantages? ...

Explain sorted File with advantages? Sorted file The sort utility shall perform one of the subsequent functions: 1.Sort lines of all the named files together and write the

Data redundancy, Data Redundancy -A lot of information is being repeated in...

Data Redundancy -A lot of information is being repeated in the relation. For instance, the information that MCS-014 is named SSAD is repetitive, address of Rahul is "D- 27, Main ro

Northwind Pty Ltd sells a variety of food products throughou, i want help t...

i want help to complete my task

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages