What is a view, Database Management System

Assignment Help:

What is a view?  Make a view of EMP table named DEPT 20, to display the employees in department 20 and their annual salary. 

Ans:  View is a virtual table that does not consists of it own data it fetch the data from the original table.

Create view DEPT20 as select * from dept; 

Where dno=20 group by dno;


Related Discussions:- What is a view

Derived horizontal fragmentation, Derived horizontal fragmentation: Some ap...

Derived horizontal fragmentation: Some applications may include a join of two or more relations. If the relations are stored at dissimilar locations, there may be a major overhead

Define instance and schema, Define instance and schema?  Instance:  C...

Define instance and schema?  Instance:  Collection of  data  kept in the  data  base  at  a  particular  moment  is  known as an Instance of the database.  Schema: The o

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 natural join, Explain natural join? Natural Join - Similar as...

Explain natural join? Natural Join - Similar as equi-join except in which the join attributes (having similar names) are not involved in the resulting relation. Only one sets

Describe embedded query language, Describe Embedded Query Language? Emb...

Describe Embedded Query Language? Embedded Query Language - A query language (e.g., SQL) can be implemented in two ways. It can be used interactively or embedded within a host

Explain the ansi -sparc schema architecture, (a) Differentiate between info...

(a) Differentiate between information and data . (b) List and briefly explain five potential benefits of the database approach compared to conventional file systems. (c) Diff

State the technique of converting the state diagram to code, The technique ...

The technique of converting the state diagram to code a) Identify all major control paths. Start from initial state; choose a path across the diagram that corresponds to normal

Illustrate package classes and associations into models, Package classes an...

Package classes and associations into models  Programs are made of separate physical units which could be edited, imported, complied or otherwise manipulated. The careful part

What is nested relational model, What is nested relational model? The n...

What is nested relational model? The nested relational model is an extension of relational model in which domains might be either atomic or relation valued.

Define cardinality and participation constraints, Define cardinality and pa...

Define cardinality and participation constraints on a relationship type, completeness constraint on generalization.        Ans: Cardinality defines the number of entities to wh

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