Ordering of tuples, Database Management System

Assignment Help:

In a relation, tuples are not inserted in any definite order. Ordering of tuples is not defined as a part of a relation definition. Though, records may be structured later according to some attribute value in the storage systems. For instance, records in PERSON table may be structured according to PERSON_ID. Such organisation or data depends on the requirement of the underlying database application. Though, for the purpose of display we may get them displayed in the sorted order of age. The following table is sorted by age. It is also worth states here that relational model does not permit duplicate tuples

PERSON

PERSON_ID      NAME                                 AGE              ADDRESS

2                           Sharad Gupta                       33                  Pocket 2, Mayur Vihar.

1                           Sanjay Prasad                      35                  b-4,Modi Nagar

3                           Vibhu Datt                           36                  c-2, New Delhi

Super Keys, Candidate Keys and Primary Keys for the Relations

As discussed in the last section ordering of relations does not matter and all tuples in a relation are unique. Though, can we uniquely recognize a tuple in a relation? Let us talk about the concepts of keys that are primarily used for the purpose as above.


Related Discussions:- Ordering of tuples

Log based recovery, Log based recovery: Let us first describe the term tran...

Log based recovery: Let us first describe the term transaction log in the context of DBMS. A transaction log is a record in DBMS that remains track of all the transactions of a dat

Inheritance, what is relationship inheritance and attribute inheritance

what is relationship inheritance and attribute inheritance

Query, Use a Set operator to create a list of academics who have written or...

Use a Set operator to create a list of academics who have written or co-written less than 5 papers and also have greater than 3 interests. List their academic number in the output.

Relationship between two tables-strategic decision making, In a job intervi...

In a job interview with a branch manager of a bank that operates in multiple Canadian provinces and the Yukon, you learn that all of the information is captured in real time in a s

DBMS, to develop elrctronic database from manual forms

to develop elrctronic database from manual forms

What is authorization graph, What is authorization graph? Passing of au...

What is authorization graph? Passing of authorization from single user to another can be shown by an authorization graph.

ER diagram, #question. acompani datdbase needs to store information about e...

#question. acompani datdbase needs to store information about employees (identified by a social security number,with salary and phone as attributes) and departments (identified by

Example of sequences, Example : Create a sequence named SEQSS that starts a...

Example : Create a sequence named SEQSS that starts at 105, has a step of 1 and can take maximum value as 2000.  CREATE SEQUENCE SEQSS START WITH 105 INCREMENT BY 1 MAX VA

Find the employee name, Example -Find the employee name, salary, department...

Example -Find the employee name, salary, department number and average salary of his/her department, for those employees whose salary is more than the average salary of that depart

Distributed Database query processing , I am doing research in this area, e...

I am doing research in this area, especially in sime join and join efficacy when several relations have been queried. Relations located in different sites. I need something like n

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