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

Schema, difference between internal schema and external schema in DBMS

difference between internal schema and external schema in DBMS

List the table modification commands in sql, List the table modification co...

List the table modification commands in SQL? A) Deletion B) Updates C) Insertion D) Update of a view

Failures and recovery, Failures and Recovery In practice various things...

Failures and Recovery In practice various things might occur to prevent a transaction from completing. Recovery methods are used to bring database, which does not satisfy consi

What is property - properties of a database, What is property - properties ...

What is property - properties of a database ? It is an integrated collection of logically related records. It consolidates separate files into a common pool of data records and

State about the use case diagram, State about the Use Case Diagram A u...

State about the Use Case Diagram A use case diagram represents a set of use cases, actors and their relationships. These diagrams shall be used to model context or requirement

DBMS, what is specialization?

what is specialization?

What you understand by client-server environment, Problem: a) Briefly d...

Problem: a) Briefly describe what you understand by Client-Server environment b) The File Server is a simple form of Client-Server. Describe the principles of the File Serve

Explain the disadvantages of a file processing system, Explain the disadvan...

Explain the disadvantages of a file processing system? Ans: Disadvantages of File Processing Systems include: 1) Data Redundancy 2) Data Inconsistency 3) Difficult to acce

Vertical fragmentation, Vertical Fragmentation- Vertical fragmentation grou...

Vertical Fragmentation- Vertical fragmentation groups together only those attributes in a relation that are used jointly by various important transactions. A vertical fragment is d

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