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!
Define entity integrity and referential integrity. How does SQL allow specification of these?
Ans: Entity Integrity Rule- If the attribute A of relation R is a prime attribute of R after that A cannot accept null values.
Referential Integrity Rule- In referential integrity, it is made sure that a value that appears in one relation for a given set of attributes as well appears for a particular set of attributes in another relation.
In SQL, referential integrity and entity integrity rules are implemented as constraints on the relation known as reference Key constraint and primary Key constraint correspondingly.
These constraints can be fixed with relation at the time of creation of the relations or after the creation of the relations by altering the definition of the relations. For instance:
One-way Associations When an association is traversed only in the one direction, then it is implemented as a pointer i.e.an attribute which contains an object reference. If mu
Produce a set of relations (equivalent to the Finkelstein entity list) in third normal form (3NF) from the following un-normalised relation. You must use the Finkelstein methodolog
What are the Objectives of object design After going through this unit, you could be able to: explain steps of object design; discuss algorithms that reduce costs;
Is it mandatory to declare all the tables in Report by the key word tables for all the tables that exist in the structure of LDB, and are being explained in the Database part of LD
The users who use easy-to-use menu are called ? The users who use easy to use menu are called as Naïve users.
Special comparison operator used in where Clause a. between. ...and...It gives range among two values (inclusive) Example: SELECT ENAME, SAL FROM EMP WHERE SAL BETWE
Performance of Various Concurrency Control Mechanisms
Outer Join: The use of Outer Join is that it still joins those tuples that do not have matching values in common columns are also contained in the result table. Outer join places
cardnality ratio for humanresource mangement system
Project Description: I would like to get a database of a website which has clients email name and phone number. If you are able to get information from a website, by entering
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