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

Explain transaction manager and their work, Explain Transaction manager and...

Explain Transaction manager and their work? Transaction Manager: Ensure the database remains in a constant (correct) state despite system failure, and in which concurrent trans

Differentiate between key and superkey, Differentiate between Key and super...

Differentiate between Key and superkey? Key and superkey - A key a single attribute or a combination of two or more attributes of an entity set in which is used to identify o

Selective replication-data replication, Selective replication: This is a c...

Selective replication: This is a combination of generating small fragments of relation and replicating them rather than a entire relation. The data should be fragmented on require

Create a query to produce single output-er model, This assignment concerns ...

This assignment concerns the Research database. The database ER model is shown above, where attributes are omitted for clarity. The relational model for the database is: Departm

What is identity, What is Identity? Identity (or AutoNumber) is a colum...

What is Identity? Identity (or AutoNumber) is a column that automatically produces numeric values. A start and increment value can be set, but most DBA leave these at 1. A GUID

Database incident table, The Incident table, with an auto-incrementing in...

The Incident table, with an auto-incrementing incident number, etc, looks like: incident_num reporter date time incide

Write short notes on transaction state, Write short notes on transaction st...

Write short notes on transaction state? A transaction may not always complete its implementation successfully such a transaction is termed aborted A transaction must be in o

What is a state chart diagram, What is a state chart diagram? State dia...

What is a state chart diagram? State diagrams (State Chart Diagram) explain all possible states that a particular object can get into, and how object's state changes as result

What are the disadvantages of file-processing system, What are the disadvan...

What are the disadvantages of file-processing system?  Ans: The Disadvantages of File-Processing System a. Data redundancy and inconsistency - Data redundancy means not nece

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