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

What is system r, What is System R? What are its two major subsystems? ...

What is System R? What are its two major subsystems? System R was intended and developed over a period of 1974-79 at IBM San Jose Research Center. It is a prototype and its pur

What are the factors into account when choosing a raid level, What are the ...

What are the factors to be taken into account when choosing a RAID level? A) Monetary cost of extra disk storage requirements. B) Performance requirements in terms of number

Evaluate the null hypothesis, 1.Suppose you are given a dataset that consis...

1.Suppose you are given a dataset that consists of a random sample of tasters, on which the following variables were obtained: (y) Zpref = taste preference for green beans store

Explain the two constraints check and foreign key in sql, Explain the two c...

Explain the two constraints, check and foreign key in SQL along with an example for each. Give the syntax. CHECK constraint - CHECK constraint specifies an expression which

Explain generalization and aggregation in e_r diagram, Explain the concept ...

Explain the concept of generalization and aggregation in E_R diagrams. Give one example for each one of them? Generalization: Consider extending the entity set account throug

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

Give short note on the following terms- dirty pages and etl, Give short not...

Give short note on the following terms:Dirty pages and ETL a.) Dirty pages. These are buffer pages which comprise modifications which haven't been written to disk. b.

What is an entity relationship model, What is an entity relationship model?...

What is an entity relationship model? The entity relationship model is a set of basic objects known as entities and relationship between those objects. An entity is a thing or

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