Define a view and a trigger, Database Management System

Assignment Help:

Define a view and a trigger. Construct a view for the above relations that have the information about suppliers and the elements they supply. The view holds the S#, SNAME, P# , PNAME renamed as SNO,  NAME, PNO,  PNAME.

View - A view is a virtual table that is based on the one or more physical tables and/or views. Instead, a  view  is  a  named  table  which  is represented,  not  through  its  own physically separate stored data, but through its definition in terms of other named tables (base tables or views).

Trigger - A trigger is a procedure which is automatically invoked through the DBMS in the response to specified modification to the database. Triggers might be used to supplement declarative referential integrity, to enforce multifaceted business rules or to audit changes to data.

Command:

CREATE VIEW SUP_PART (SNO, NAME, PNO, PNAME) AS

SELECT S.S#, SNAME, P.P#, PNAME

FROM S, SP, P

WHERE S.S# = SP.S# AND P.P# = SP.P#

 


Related Discussions:- Define a view and a trigger

Define deadlock prevention, Define Deadlock prevention These protocols...

Define Deadlock prevention These protocols make sure that the system will never enter a deadlock state. There are two methods to deadlock prevention. One approach makes sure t

Need point of sale software for pizza restaurant, Project Description: N...

Project Description: Need Point of Sale software for pizza restaurant. Delivery and take out service, client's database, inventory control, order history, last order, order from

Explain the aggregation implies concurrency, Explain the Aggregation implie...

Explain the Aggregation implies concurrency Concurrency actually is: This in objects can be identified by the way they change state. Present objects can change state independen

Write modified version of transfer that avoids deadlock, Your OS has a set ...

Your OS has a set of queues, each of which is protected by a lock. To enqueue or dequeue an item, a thread must hold the lock associated to the queue. You need to implement an a

Describe the primary key functions, Describe the primary key functions? ...

Describe the primary key functions? Primary Key : The primary key is an attribute or a set of attributes in which uniquely identify a specific example of an entity. Every entit

Explain interblock gap, Explain Interblock gap? Interblock Gap - A trac...

Explain Interblock gap? Interblock Gap - A track of a disk is separated into equal-sized disk blocks. Blocks are separated through fixed-size gaps, called as interblock gaps th

Optimistic concurrency control, Optimistic Concurrency Control Is locki...

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

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

What is distributed system, What is Distributed system ? Distributed S...

What is Distributed system ? Distributed System - A distributed system consists of a number of processing parts in which are interconnected through a computer network and in

What is known as a search key, What is known as a search key? An attrib...

What is known as a search key? An attribute or set of attributes used to look up records in a file is known as a search key.

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