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!
Differentiate between various levels of data abstraction?
Data Abstraction - Abstraction is the procedure to hide the irrelevant things from the users and represent the relevant things to the user. Database systems are frequent used through non-computer professionals so in which the complexity must be hidden from database system users. This is done through defining levels of abstract as that the database may be viewed; there is logical view or external view, conceptual view and internal view or physical view.
1. External View - This is the highest level of abstraction as seen through a user. It describes only the part of whole database, that is relevant to a particular user.
2. Conceptual View - This is the next higher stages of abstraction that is the sum total of Database Management System user's views. It elaborates what data are in fact stored in the database. It contains information about whole database in terms of a small number of associatively easy structure.
3. Internal View - This is the lowest level of abstraction. It elaborates how the data are physically stored
What is advantage of two-way association? Two-way association advantages are following: a) Independent of the classes. b) Useful for existing predefined classes that are
Consider a relation s over the attributes A and B with the following characteristics: 5,000 tuples with 10 tuples per page A 2-level B+ tree index on attribute
What are the advantages of embedded query language? Give an example of an embedded SQL query. Embedded query language - SQL could be implemented within two ways. It can be us
What it creates while a primary key is combined with a foreign key? It creates Parent-Child relation ship between the tables that connect them while a primary key is combined w
Question (a) Differentiate between the following terms: (i) Distributed Database v/s Distributed Database management System (ii) Homogeneous Distributed Database v/s Hete
Related fields in a database are grouped in which form? Related data fields in a database are grouped to form a data record. (A record is a collection of related fields)
why are older data models are being replaced by new data models
What do you mean by DBMS? What is its need and what are its goals. Explain? OR Explain Data Base Management System? Sol. Database management system is a
PART MARKING: We will only mark TWO of the four questions below but you must submit answers to all four. We will choose the questions we mark randomly and we will supply you with
Improved performance: As the data is located near the site of its demand, and given the inherent parallelism because of multiple copies, speed of database access may be good for di
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