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 is completeness constraint on generalization, What is completeness con...

What is completeness constraint on generalization? Define the variation between total and partial design constraint. Give an example each.       Ans: Completeness Constraints

What is a view in sql and when can views be updated, What is a view in SQL?...

What is a view in SQL? When can views be updated? A view is a virtual table which consists of columns from one or more tables. Through it is same to a table; it is stored in

How many types of data independence have, Types of data independence D...

Types of data independence Data independence can be classified into the following two types: Physical Data Independence: This means that for any change made in the physi

How is the database organised in oracle, How is the database organised in O...

How is the database organised in Oracle? Database organized within Oracle in terms of table and table holds attributes and values. A database consists of one or more logical

What is key, What is key ? Key - A single attribute or a combination of...

What is key ? Key - A single attribute or a combination of two or more attributes of an entity set which is used to recognize one or more instances (rows) of the set (table) is

Decompose the table with the functional dependencies, Decompose the table w...

Decompose the table with the following description and functional dependencies into a set of equivalent tables normalized to 3NF or BCNF. This database stores records from a (ve

Adjustments are required to increase chances of inheritance, What types of ...

What types of adjustments are required to increase chances of inheritance. a)   Some attributes can be added or ignored in  the base class operation  b) Some changes can be

What is meant by data-transfer rate, What is meant by data-transfer rate? ...

What is meant by data-transfer rate? The data-transfer rate is the rate at which data can be retrieved from or kept to the disk.

Read-set(t) and timestamps-optimistic concurrency contents, read-set(T) : E...

read-set(T) : Each data items that are read by a transaction T Timestamps : for all transaction T, the start-time and the end time are reserved for all the three phases.

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