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

Why does a dbms query language is designed, Why does a DBMS query language ...

Why does a DBMS query language is designed? A DBMS query language is designed to support end users who use English-like commands. support in the development of complex applicat

Explain differance between primary and secondary storage, Explain differanc...

Explain differance between Primary and secondary storage ? Primary and secondary storage Computer storage is classified within primary(main) memory and secondary(per

What is meant by data-transfer rate, What is meant by data-transfer rate? ...

What is meant by data-transfer rate? The data-transfer rate is the rate at which data can be retrieved from or kept to the disk.

How to design a formal and exact model, How to design a formal and exact mo...

How to design a formal and exact model How to design a formal and exact model of real-world problems by applying findings of analysis phase of OMT. The object design phase find

Customer service, as a customer service employee, explain five measures you...

as a customer service employee, explain five measures you would recommend a displeased student to patronise a school canteen

Illustrate the diagram - association as a cache, Association as a cache ...

Association as a cache This association must be updated when any new element is added to it, but testing for overlap using association is more efficient.    Figure:

Illustrate the fifth normal form, Fifth Normal Form (5NF) These relatio...

Fifth Normal Form (5NF) These relations still have a difficulty. While defining the 4NF we mentioned that all the attributes depend upon each other. Whereas creating the two ta

Write short notes on relational constraints, Write short notes on relationa...

Write short notes on relational constraints? Relational Constraints are: 1. NOT NULL 2. Unique 3. Primary key 4. Foreign key 5. Table check

Explain the fundamental concepts of object-orientation, Explain the Fundame...

Explain the Fundamental concepts of object-orientation Software developers, data base administrators (DBAs) need to be familiar with fundamental concepts of object-orientation.

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