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:
Ancestry database records information about family trees . Following information is recorded about each person: FIRSTNAME first name SURNAME surname MNAME maiden name (if
Consider a database schema consisting of four relations, whose schemas are: Product (maker, model, type) PC (model, speed, ram, hd, price) Laptop (model, speed, ram, hd, s
Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pictori
Define the terms entity, attribute, role and relationship between the entities, giving examples for each of them. Ans: Entity: An entity is a "thing" or "object" in th
Explanation on Data Sharing?
Determine the Persistent object Persistent object can be stored in one of the following: Files Cheap, permanent, simple storage Low level (Write, Read) Ap
Define physical image of a global relation at a site
Why is need for the multiple access paths?
Explain Recursive relationship type? Recursive relationship type: A recursive relationship is one in that the similar entity participates more than once in the relationship
Secondary Indexes Let consider the student database and its clustering index and primary (only one will be applicable at a time). Now consider the state when the database is to
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