Explain retrieval in qbe, Database Management System

Assignment Help:

Explain retrieval in QBE?

Retrieval in QBE : A "GUI" for expressing queries.

  1. Based on the Domain Relational Calculus (DRC)
  2. Actually invented before GUIs.
  3. Very convenient for simple queries.
  4. Awkward for complex queries.
  5. QBE and IBM trademark.

But has influenced many projects Especially PC Databases: Paradox, Access, etc.


Related Discussions:- Explain retrieval in qbe

What are the four main characteristics of the database, What are the four m...

What are the four main characteristics of the database approach? The four major characteristics of the database approach are: 1. Self-describing nature of a database system. 2.

Accessing information permissions users, Accessing information about permis...

Accessing information about permissions to all users- Object level permissions: With the use of data dictionary you can see the permissions to user. Let us get the table name fro

Unix System Administration, What Command You Use What Day of the week were ...

What Command You Use What Day of the week were you born

Objectives of database manangement system, OBJECTIVES After going thro...

OBJECTIVES After going through this unit you should be capable to: Explain the File Based system and its limitations; Explain the structure of DBMS; Explain the

Explain query tree represent relational algebra expression, How does a quer...

How does a query tree represent a relational algebra expression?      Ans: This includes transforming an initial expression (tree) into an equivalent expression (tree) that is

What is meant by heuristic optimisation, What is meant by heuristic optimis...

What is meant by heuristic optimisation?  Discuss the main heuristics that are applied during query optimisation.  Ans:  In heuristic optimization, heuristics are employed to r

N-ary relationship, For every n-ary relationship type R where n>2, we make ...

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

Related fields in a database are grouped in which form, Related fields in a...

Related fields in a database are grouped in which form? Related data fields in a database are grouped to form a data record. (A record is a collection of related fields)

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