Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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
Determine the Persistent object Persistent object can be stored in one of the following: Files Cheap, permanent, simple storage Low level (Write, Read) Ap
Use of partial data by applications : In common, applications work with views rather than whole relations. Thus, it may be more appropriate to work with subsets of relations rather
what are the purposes of dbms in details
What is it ?
What are the states of transaction? The states of transaction are:- a) Active b) Partially committed c) Failed d) Aborted e )Committed f) Terminated
Explain four causes for failures in data warehouse projects
What is a database? Database - Basically in simple terms A database is a collection of inter related data and/or information stored so which it is available to several users
wh
State the definition of association An association is a structural relationship which specifies that objects of one thing are connected with objects of another. In UML, asso
Control Files : The redo and control files logs support the rest of the architecture. Every database must have at least one control file, although you have more than one to guard
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd