Explain record based logical models, Database Management System

Assignment Help:

Explain Record Based Logical Models?

Record-Based logical Models: Also define data at the conceptual and view levels. Unlike object-oriented models, are used to state overall logical structure of the database, and gives a higher-level description of the implementation. Named so since the database is structured in fixed-format records of various types. Each record type defines a fixed number of fields, or attributes. Each field is commonly of a fixed length (this simplifies the implementation). Record-based models do not involved a mechanism for direct representation of code in the database. Separate languages related along with the model are used to express database queries and updates. The three most widely-accepted models are the relational, network, and hierarchical.


Related Discussions:- Explain record based logical models

Write the syntax of creating an index, Write the syntax of creating an INDE...

Write the syntax of creating an INDEX ? Syntax of Creating an Index: CREATE [BITMAP] [UNIQUE] INDEX ON ( [, ] . . .);

Differentiate between static hashing and dynamic hashing, Differentiate bet...

Differentiate between static hashing and dynamic hashing.  Ans: Static Hashing comprises the number of primary pages in the directory fixed. So, while a bucket is full, we requ

What are the reasons for having variable length records, What are the reaso...

What are the reasons for having variable length records? What are the various ways to store variable length records? Variable-length records arise in a database in various wa

What is entity in dbms, What is entity in DBMS? Entity: A DBMS entity i...

What is entity in DBMS? Entity: A DBMS entity is either a thing in the modelled world or a drawing element in an ERD.

multiple-mode locks, Multiple-mode locks : It offers two locks: exclusive ...

Multiple-mode locks : It offers two locks: exclusive locks and shared locks. But why do we require these two locks? There are a lot of transactions in the database system that neve

What are the uses of functional dependencies, What are the uses of function...

What are the uses of functional dependencies? To test relations to see whether they are legal under a given set of functional dependencies. To state constraints on the set

What is a view in sql and when can views be updated, What is a view in SQL?...

What is a view in SQL? When can views be updated? A view is a virtual table which consists of columns from one or more tables. Through it is same to a table; it is stored in

Data manipulation language, Question 1 Discuss about second normal form an...

Question 1 Discuss about second normal form and third normal form Question 2 Write short note on                        1) Data Manipulation Language 2) Data Definition La

Having clause-data manipulation language, Having clause This clause...

Having clause This clause is used for producing conditions on grouped information. Example: Find maximum salary and department number of those departments where maxim

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