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!
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
For every n-ary relationship type R where n>2, we make a new table S to represent R. We contain as foreign key attributes in s the primary keys of the relations that show the parti
If the deletion violates referential integrity constraint, then three alternatives are available: Default option: - refuse the deletion. It is the job of the DBMS to describ
What is a trigger
Attribute Preservation This is a easy and obvious necessity that includes preserving all the attributes that were there in the relation that is being decomposed.
Software failures : In such cases, a software error abruptly stops the implementation of the current transaction (or all transactions), therefore leading to losing the state of pr
What is meant by object-oriented data model? The object-oriented paradigm is based on encapsulation of data and code related to an object in to a one unit, whose contents are n
Describe about Use Case and external case in DFD The processes are transformed those into the Use Case and external case in DFD has same characteristics which of an actor in O
Explain entity integrity and referential integrity rules within relational model. Show how these are realized in SQL? Entity Integrity Rule - No primary key value could be nu
Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.
A relation instance indicates as r is a collection of tuples for a given relational schema at a exact point of time. A relation state r of the relation schema R (A 1 ,A 2 ,.....
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