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

Unix System Administration, What Command You Use What Day of the week were ...

What Command You Use What Day of the week were you born

Describe logical data independence, Describe logical data independence ? ...

Describe logical data independence ? Logical Data Independence - It is the capacity to modify the conceptual schema without having to change external schemas or application p

Data control, Data Control The data control mostly refers to commands that...

Data Control The data control mostly refers to commands that permit system and data privileges to be passed to several users. These commands are usually available to database admi

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

What is relationship instance, What is relationship instance ? Relation...

What is relationship instance ? Relationship Instance - A relationship is a relation between two or more entities. An instance of relationship set is a set of relationships.

What is class diagram, Class Diagram A class diagram is required to su...

Class Diagram A class diagram is required to support functional necessity of system. In a static design view, class diagram is used to model vocabulary of the system, simple c

Extend the database, Now that she understands more about the benefits of da...

Now that she understands more about the benefits of databases, the play-scheme manager would like to extend the play-scheme database to include data for schools and instructors as

State in detail about data flow diagram, What is a Data Flow Diagram?  ...

What is a Data Flow Diagram?  Data Flow Diagram: A data flow diagram is the graph that shows flow of data values from their sources in objects in the course of processes whic

A basic model of database access control, A basic model of Database Access ...

A basic model of Database Access Control Models of database access control have grown out of previous work on protection in operating systems. Let us talk about one simple mode

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