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:
Introductory course and so does not require any fancy coding. I will provide a guidance document to help you in producing the solutions.
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
What are the various symbols used to draw an E-R diagram? Explain with the help of an example how weak entity sets are represented in an E-R diagram. Various symbols used to d
Question: AirwaysCentre, an international airline booking company currently uses a relational database system for their operations, which includes the following relations: P
coventions for displaying an ER schema as ER diagram
What is recovery management component? Ensuring durability is the responsibility of a software component of the base system known as the recovery management component.
What is Asterisk in SQL? Asterisk (*): In SQL, the columns for all the tables and views in the FROM clause will be displayed.
What is Object Oriented model? This model is based on collection of objects. An object has values stored in instance variables with in the object. An object also having bodies
Using the questions found at the end of Chapter 9 in your textbook, complete this homework activity. Students will submit a Word document answering questions 2, 3, and 4.
Describe the statement in SQL which allows to change the definition of a table? In SQL Alter statement is used to allow the changes the definition of a table.
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