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!
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.
What is candidate key? Candidate Key - A candidate key of an entity set is a minimal superkey, which uniquely identifies each row in the relation.
Explain about primary key Primary Key: It is one of the candidate keys that are taken to be the recognizing key for the entire table. E.g. although there are two candidate ke
i need help with creating database system for a library
Question 1 Discuss on transmission impairments Question 2 What is framing? Question 3 Write a note on 10Base2 10Base- T Question 4 Explain the rev
Which method is used to key transformation ? A hash method is used to key transformation.
A relationship set is a set of relationships of the similar type. For example, let consider the relationship among two entities sets course and student. Collection of all the in
Relationship between Security and Integrity: Database security usually refers to access, while database integrity refers to avoidance of accidental loss of consistency. But usually
What is meant by mean time to failure? The mean time to failure is the amount of time that the system could run continuously without failure.
Explain the Attribute inheritance Ans: Throughout the rendering of the objects in a view, attribute sets of objects higher in the view hierarchy are inherited via objects below
What is ODBC ? ODBC - Open DataBase Connectivity which is also denoted by ODBC enable the integration of SQL along with a common-purpose programming language. ODBC expose data
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