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
Conversion of entity sets: I) For every strong entity type E in the ER diagram, we make a relation R containing all the easy attributes of E. The relation R pri
Column Constraints: NOT NULL, UNIQUE, CHECK, PRIMARY KEY, DEFAULT, REFERENCES, On delete Cascade : Using this key whenever a parent row is removed in a referenced
Explain the cartesian product in Database Management System
List some instances of collection types? a) sets b) arrays c) multisets
What do you mean by persistence? How you will make your data persistent? Persistent data is the data, which has a longer lifetime than program which has created it. Enabling th
What is the purpose of tables, private synonyms and public synonyms? If there are multiple objects of similar name on an Oracle database, that order are they accessed in? The r
The Maximum no of key fields that can be used in a header is?? 50
Project Description: We have purchased facebook style chat software which we are using with our site. It is prepared in PHP but the rest of the site is developed asp.net. Iss
INTRODUCTION Databases and database systems have become an essential part of our daily life. We encounter many activities that involve some interaction with a database almost
What is system log? What are the entries? Ans: The system log that is generally written on stable storage contains the redundant data required to recover from volatile
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