Views-data control, Database Management System

Assignment Help:

Views

A view is like a window by which data from tables can be changed or viewed. The table on which a view is based is known as Base table. The view is stored as a SELECT statement in the data dictionary. When the user needs to retrieve data, using view. Then the following steps are defined.

1)  View definition is finding from data dictionary table. For example, the view definitions in oracle are to be finding from table name USER-VIEWS.

2)  Checks access privileges for the view base table.

3)  Changes the view query into an equivalent operation on the underlying base table

 

 


Related Discussions:- Views-data control

What does the cardinality ratio specify, What does the cardinality ratio sp...

What does the cardinality ratio specify? Mapping cardinalities or cardinality ratios state the number of entities to which another entity can be associated. Mapping cardinaliti

Explain briefly concurrent task by taking an example, Explain briefly concu...

Explain briefly concurrent task by taking an example. Concurrent Task- The concurrent occurrence of more than one event is called concurrent task. Operating systems can handl

Define data independence, Data independence seems that "the application is...

Data independence seems that "the application is independent of the access strategy and storage structure of data". In other words, the ability to change the schema definition in o

By the relations get details of employees working in sql, Consider the rela...

Consider the relations: PROJECT(proj#,proj_name,chief_architect) EMPLOYEE(emp#,emp_name) ASSIGNED(proj#,emp#) Use relational algebra to express the subsequent queries: (i) Get

Mysql, he SQL query that will return the order number, quantity ordered, pr...

he SQL query that will return the order number, quantity ordered, price each and total cost of an order (quantity * price each) from the order details table. Label the calculated c

Define shared locks, Define Shared locks? Ans: Shared lock: Throughout ...

Define Shared locks? Ans: Shared lock: Throughout concurrent execution of transactions, earlier than a transaction can access a data item, it has to obtain a lock on it. Now he

What is conceptual model, What is conceptual model ? A conceptual model...

What is conceptual model ? A conceptual model is a independent of both hardware and software.

Define clause in sql to specify query result must be sorted, The clause in ...

The clause in SQL which specifies that the query result should be sorted in ascending or descending order based upon the values of one or much more columns is Ans : Order by

Describe substring comparison in sql, Describe substring comparison in SQL....

Describe substring comparison in SQL. For the relation Person (name, address), write a SQL query that retrieves the names of people whose name starts along with ‘A' and address co

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