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!
List two restrictions that are applied on the modification (updation, insertion or deletion) of base tables through view.
Ans: The two restrictions are:
1. If a view does not consist of primary key and/or at least one of the attributes along with the NOT NULL constraint which do not have default values specified, is not updatable. This restriction is needed because if we are inserting any row in the view than all attributes not included in view of the base relation are will be denoted by the NULLs if any default value is not specified. In this type of case, if any attribute is set as NOT NULL or primary key, then it should not be NULL, and the insertion will be violating the constraints.
2. If a view defined by using grouping and/or aggregate functions, is not updatable. This restriction is also needed because, if we want to modify the base relation by view then we are not in the position to identify that tuple(s) will be modified in the group in what way.
#question.ERD of any car
It is mandatory that for every table in the LDB hierarchy there should exist one GET statement in the report. False. It is not essential.
Differentiate sub-class and super-class? The specialization of a class is known as subclasses.eg: employee is a subclass of person and teller is a subclass of employee. Convers
What are stored and derived attributes? Stored attributes: The attributes keeps in a data base are known as stored attributes. Derived attributes: The attributes that are de
Determine the advantage of object-orientation Finally, object-orientation has advantage of continuity throughout analysis, persistent representation and design implementation.
what is file organization? what are file organization techniques.explain in detail? explain random file organization technique, multikey file organization technique?what is indexin
Consider the relations given below Borrower (id_no, name) Book (accno., title, author, borrower_idno) (a) Define the above relations as tables in SQL forming real world assumptio
Project Description: The work is about founding the best skilled person for the job. I will give you the job description. Skills required are Data Entry, Database Administrat
What are the reasons for having variable length records? What are the various ways to store variable length records? Variable-length records arise in a database in various wa
Q. With the help of a suitable diagram gives module wise explanation of system architecture of DBMS. Sol. A Database management is a collection of interrelated data and col
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