Creating views with check option-data control, Database Management System

Assignment Help:

Creating views with check option: This option limits those updates of data values that cause records to go off the view. The following instance tells this in more detail:

Example: To produce a view for employees of Department = 30, such that user cannot alter the department number from the view:

CREATE OR REPLACE VIEW EMPD30 AS

SELECT EMPNO EMPL_NUM, ENAME NAME, SAL SALARY FROM EMP

WHERE DEPTNO=30

WITH CHECK OPTION;

 

Now the user cannot alter the department number of any record of view EMPD30. If this change is permitted then the record in which the change has been made will go off the view as the view is only for department-30. This restricted due to use of WITH CHECK OPTION clause

 


Related Discussions:- Creating views with check option-data control

Create database and define relationships between tables, Instructions: ...

Instructions: Follow the instructions below for completing this project: 1. Creating the Database: · Use the physical table descriptions given below to define and create each t

Identification of concurrency, Identification of concurrency Identifica...

Identification of concurrency Identification of concurrency: Dynamic model identifies concurrency. Two objects are said to be parallel (concurrent) if they can receive events a

Cartisian product, Explain the cartesian product in Database Management Sys...

Explain the cartesian product in Database Management System

Which element in the database can modified by changing, Which element in th...

Which element in the database can modified by changing the data dictionary? Data elements in the database can be changed or modified through changing the data dictionary.

What is an e-r model and draw an e-r diagram for the company, What is an E-...

What is an E-R model? Draw an E-R Diagram for the company database with following Descriptions? The company is organized within departments. Each department has a unique name a

Find out the names of all employees from database, Find out the names of al...

Find out the names of all employees who work for first Bank Corporation from database. SELECT EMPLOYEE_NAME FROM WORKS WHERE COMPANYNAME = ‘First Bank Corporation';

Balance transfer, Scenario 1: Power goes out after the first instruction. ...

Scenario 1: Power goes out after the first instruction. What happens?

Which operations need the participating relations to union, Which operation...

Which operations need the participating relations to be union compatible? A UNION, INTERSECTION and DIFFERENCE operations need the participating relations to be union compatibl

Client dbms, i need to submit in this topic.

i need to submit in this topic.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd