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

Mention the purpose of sid and sod lines, Mention the purpose of SID and SO...

Mention the purpose of SID and SOD lines SID (Serial input data line): It is an input line by which the microprocessor accepts serial data. SOD (Serial output data line)

Define control files, Control Files : The redo and control files logs supp...

Control Files : The redo and control files logs support the rest of the architecture. Every database must have at least one control file, although you have more than one to guard

Modify - referential integrity, Update or Modify operation alters the exist...

Update or Modify operation alters the existing values. If these operations alter the value that is the foreign key also, the only check need is the similar as that of the Insert op

Draw an entity-relationship model, Draw an Entity-Relationship model for ...

Draw an Entity-Relationship model for the relational schema given in the Appendix. Show all the entities, relationships, relationship names, and attributes and also underline the

Sql, sql is relationally complete-justify

sql is relationally complete-justify

Improved availability, Improved availability: The data in a distributed sys...

Improved availability: The data in a distributed system may be replicated so that it is at more than one site. Thus, the failure of a node or a communication link does not necessar

gaps in sequence values can happen when-sequences, Gaps in sequence values...

Gaps in sequence values can happen when: -     A rollback happens that is when a statement changes are not accepted. -     When the system crashes -     When a sequence i

The file based system in dbms, The File Based System File based systems...

The File Based System File based systems are an early attempt to computerise the manual filing system. For example, a manual file can be set up to hold all the correspondence r

What is called query processing, What is called query processing? Query...

What is called query processing? Query processing refers to the range of activities included in extracting data from a database.

The natural join is equal to which product, The natural join is equal to wh...

The natural join is equal to which product? The natural join is equal to Combination of projection and Cartesian product

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