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!
Describe entity referential integrity and integrity. Give an example of each.
Entity Integrity Rule - If there is a attribute A of relation R is a prime attribute of R then A cannot accept null values.
Referential Integrity Rule - In referential integrity, it is ensured in which a value in which appears in one association for a given set of attributes also appears for a certain set of attributes in another relation.
For example:
Roll No is the primary key within the relation STUDENT and Roll No + Course is the primary key of the relation GRADE. (Entity Integrity) Roll No in the relation GRADE (child table) is a foreign key, which is referenced from the relation STUDENT (parent table). (Referential Integrity).
What does the extract statement do in extract datasets? The data is written to virtual memory by extract commands.
Discuss deferred update technique of recovery. What are the advantages? Ans: The deferred update methods do not physically update the database on disk till after a transact
Gaps in sequence values can happen when: - A rollback happens that is when a statement changes are not accepted. - When the system crashes - When a sequence i
(a) Data Mining Process : In the context of this cluster analysis project , and in your own words , explain how you would execute the first stage of data mining, namely the "P
A database is a set of data. But, is the data kept in a database trustworthy? To answer that query we must first answer the question. What is integrity? Integrity simply means t
What is transaction? Transaction is a unit of program implementation that accesses and possibly updated several data items.
Preliminary entities and attributes of human resourse management database management system
properties of derirable decomposition
The Concurrent Transactions Almost every commercial DBMS support multi-user environment. Therefore, allowing multiple transactions to proceed concurrently. The DBMS must make
Data independence seems that "the application is independent of the access strategy and storage structure of data". In other words, the ability to change the schema definition in o
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