What is E-R model, Database Management System

Assignment Help:

E-R Model

This data model is based on real world that consists of basic objects named entities and of relationship among these objects. Entities are illustrated in a database by a set of attributes. An Entity - Relationship model is an abstract way to define a database. It generally starts with a relational database, which loads data in tables. Some of the data in these tables point to data in other tables - for instance, your entry in the database would point to various entries for each of the phone numbers that are yours. The ER model would define that you are an entity, and each phone number is an entity, and the relationship between the phone numbers and you is 'has a phone number'. Diagrams prepared to design these relationships and entities are called E-R diagrams or entity-relationship diagrams.

 

955_ER Model.png


Related Discussions:- What is E-R model

What do you understand by data ware house, Question 1: Define the term ...

Question 1: Define the term business intelligence tools? Briefly explain how the data from one end gets transformed into information at the other end? Definition Exp

List the reg-no of vehicles owned in relational algebra, Given the followin...

Given the following relations Vehicle (Reg_no, make, colour) Person(eno, name, address) Owner(eno, reg_no) Write expressions in the relational algebra to answer the following

Explain network model in dbms, Explain Network Model in DBMS? Network ...

Explain Network Model in DBMS? Network Model - It was formalised within the late year of 1960s through the Database Task Group of the Conference on Data System Language (DBTG

Explain function group, What is a function group? A function group is ...

What is a function group? A function group is a collection of logically related modules that share global data with every other.  All the modules in the group are contained in

Define single value and multivalued attribute, Define Single Value and Mult...

Define Single Value and Multivalued attribute Single value attribute comprise a single atomic value for an entity and multivalued attribute may have much more than one value f

What is a database, What is a Database? To know what database is, we ha...

What is a Database? To know what database is, we have to start from data, which is the basic building block of any DBMS. Data: Facts, figures, statistics etc. having no pa

Define dbms, Define DBMS? DBMS: database management system (DBMS) is co...

Define DBMS? DBMS: database management system (DBMS) is computer software designed for the reason of supervision databases based on a variety of data models.

What is the difference between where and having clauses, What is the differ...

What is the difference between WHERE and HAVING clauses?. Predicates in the WHERE clause applies to every tuple while the predicate in the HAVING clause applies to groups.

What is object identity, What is object identity? An object retains its...

What is object identity? An object retains its identity even if some or all the values of variables or explanations of methods change overtime.

Datawarehouse, 1) Define a job scheduling strategy that will meet business ...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

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