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

Benefits abd drawback of hashed file organisation, Benefits of Hashed file ...

Benefits of Hashed file Organisation 1.      Insertion or search on hash-key is quick. 2.      Best if equality search is required on hash-key. Drawbacks of Hashed file

Define entity integrity and referential integrity, Define entity integrity ...

Define entity integrity and referential integrity.  How does SQL allow specification of  these? Ans: Entity Integrity Rule- If the attribute A of relation R is a prime attribut

What is known as sequential file organization, What is known as sequential ...

What is known as sequential file organization? In the sequential file organization, the records are kept in sequential order, according to the value of a "search key" of every

Describe entity referential integrity and integrity, Describe entity refere...

Describe entity referential integrity and integrity. Give an example of each. Entity Integrity Rule - If there is a attribute A of relation R is a prime attribute of R then A

Create a view containing name and number of department, Create a view emp_d...

Create a view emp_dep containing e_name and number of dependents from the tables employee and dependent of (i) CREATE VIEW emp_dept AS SELECT ename, COUNT(*) FROM employee, dep

Concurrency control, Give the two reasons for allowing concurrency

Give the two reasons for allowing concurrency

When is update_statistics command used, When is UPDATE_STATISTICS command u...

When is UPDATE_STATISTICS command used? - When processing of large data is done, this command is used. - Whenever large number of modification, deletions or copy takes place

In which format database schema is written, In which format database schema...

In which format database schema is written ? Data base schema is written in the DDL format.

Create a database for store company details, You group has been hired by  T...

You group has been hired by  TrainingrUs.com to keeps track of training revenues. TrainingrUS.com wants you to keep scheduling. COURSE table contains following information:

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