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
What is inheritance? Inheritance is an object orientation concept that allows reusability of code / design. Basic sense of inheritance is that if one class is predefined than a
Give some encryption techniques? A) DES B) AES C) Public key encryption
Define average latency time. The average latency time of the disk is one-half the time for a full rotation of the disk.
Explain trivial dependency? Functional dependency of the form α ->β. is trivial if α C β. Trivial functional dependencies are satisfied by all the relations.
What is a data dictionary? Data Dictionary is a main source of data in a data management system. Its major function is to carry the creation and management of data definition
What are data models? Explain it detail? Entity relationship model Rectangles Ellipse Diamonds Lines Relational model Relational model use a collection
Relational Algebra is a set of basic operations used to influence the data in relational model. These operations allow the user to specify basic retrieval request. The result of re
aggregation
1. Create a subroutine that does the remote blast on the file protein.fa. 2. Pass that returned files from the blast to another subroutine that parses the output and sends it to
NEED ER DIAGRAM WITH MINIMUM ENTITY AND RELATIONSHIP of Hospital Management System
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