Attributes and tuple, Database Management System

Assignment Help:

Before we talk about the relational model in more detail, let us first define some very basic terms used in this model.

Tuple

Every row in a table shows a record and is called a tuple. A table containing 'n' attributes in a record is called n-tuple.

Attribute

 The name of every column in a table is used to interpret its meaning and is known as an attribute. Every table is called a relation.

For instance, Figure shows a relation PERSON. The columns NAME, PERSON_ID, AGE and ADDRESS are the attributes of PERSON and every row in the table represents a separate tuple (record).

 

Relation Name:  PERSON

PERSON_ID

NAME

AGE

ADDRESS

TELEPHONE

1

Sanjay Prasad

35

b-4,Modi Nagar

011-25347527

2

Sharad Gupta

30

Pocket 2, Mayur Vihar.

023-12245678

3

Vibhu Datt

36

c-2, New Delhi

033-1601138

Figure: An extended PERSON relation


Related Discussions:- Attributes and tuple

Example of relational operations, Consider the relation PERSON. If you want...

Consider the relation PERSON. If you want to display details of persons having age less than or equal to 30 than the select operation will be used as follows: σ AGE The resu

Relation instance or relation state, A relation instance indicates as r is ...

A relation instance indicates as r is a collection of tuples for a given relational schema at a exact point of time. A relation state r of the relation schema R (A 1 ,A 2 ,.....

Describe the storage structure of indexed sequential file, Describe the sto...

Describe the storage structure of indexed sequential files and their access method. Ans: Index offers a lookup capability to rapidly reach the vicinity of the desired record.

State the object design for processing, State the Object Design for Process...

State the Object Design for Processing  The object design phase comes after analysis and system design phase. The object design phase includes implementation details like as i

Stock market, need requirement analysis for database management of stock ma...

need requirement analysis for database management of stock market

Explain recovery process after system failure, Explain recovery process aft...

Explain recovery process after system failure using checkpoint. Ans: Checkpoint scheme or method is an extra component of the log based recovery system. This scheme is used to

What is normalization, What is normalization? It is a method of analysi...

What is normalization? It is a method of analysing the given relation schemas based on their Functional Dependencies (FDs) and primary key to attain the properties (1).Minim

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