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

What is the use of keyword isa, What is the use of keyword ISA? The use...

What is the use of keyword ISA? The use of keyword ISA is to show that a class is a specialization of another class.

What is a sub-query, (a) What is a Sub-Query? (b) What is the differen...

(a) What is a Sub-Query? (b) What is the difference between a scalar sub-query and a tabular sub-query? (c) Write an equivalent SQL statement to get the Name of Product wh

MIS, We face problem of stock Opening balance and closing balance in Minus...

We face problem of stock Opening balance and closing balance in Minus

What is rdbms, What is RDBMS? Relational Data Base Management Systems (...

What is RDBMS? Relational Data Base Management Systems (RDBMS) are database management systems that maintain data records and indices in tables. Relationships may be formed and

What are the states of transaction, What are the states of transaction? ...

What are the states of transaction? The states of transaction are:- a) Active b) Partially committed c) Failed d) Aborted e )Committed   f) Terminated

Construct a generalization-specialization hierarchy, Construct a generaliza...

Construct a generalization-specialization hierarchy for a motor-vehicle sales company. The company sells motorcycles that comprise an engine number and cost; cars that have a chass

Perform an exploratory analysis on the entire dataset, Australian Bureau of...

Australian Bureau of Statistics (ABS) provides retail data for different groups and different states as well as the aggregate numbers. Table 11 " Retail Turnover, State by Industry

Transactions t1 and t2 are in a deadlock, Evaluate: a.When transactions...

Evaluate: a.When transactions T1 and T2 are in a deadlock, one of the transactions will eventually implement to completion and let the other one continue implementation. b.

Dirty reads-problems of concurrent transactions, Dirty Reads: T10 reads a ...

Dirty Reads: T10 reads a value which is updated by T9. This update has not been committed and T9 aborts. T9 T10 Value of x old value = 200

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