Map objects to a relational database? , JAVA Programming

Assignment Help:

Due to impedance mismatch between relational technology and object you need to understand the progress of mapping classes (objects) and their relationships to tables and relationships between them in a database. Classes show both behavior and data whereas relational database tables just insert data. Database schemas have keys whereas object schema does not have keys and instead use instance references to implement relationships to other objects.

 

858_Relational Database.png

 

1. Classes map to tables in a way but not directly.

2. An attribute of a class may be mapped to zero or more columns in a database. Not all attributes are consistent.

3. Some attributes of an object are objects itself. This is a recursive relationship where at some point the attribute will be mapped to more columns or zero.

4. In its simple form an attribute maps to a single column whereas each has similar type. When you prepare mapping with different kinds then you will use to be able to convert them back and forth.

 


Related Discussions:- Map objects to a relational database?

Program that receives two integer inputs from a user, Question 4 Write ...

Question 4 Write a program that receives two integer inputs from a user, an ending value, lastvalue and column, column. The program will display all numbers from 1 to lastvalue

Computer application and program, Computer application and program. Proj...

Computer application and program. Project Description: I require a project done. It is a computer desktop application program. It is not very hard. Skills required: Any

What is render kit in jsf, Component classes generally move the task of gen...

Component classes generally move the task of generating output to the renderer. All JSF components follow it. Render kit is a set of related renderers. javax.faces.render.RenderKit

The fancy new French restaurant La Food is very popu, The fancy new French ...

The fancy new French restaurant La Food is very popular for its authentic cuisine and high prices. This restaurant does not take reservations. To help improve the efficiency of the

Write javascript code to convert the number, Write JavaScript code to conve...

Write JavaScript code to convert the number 236.2363611111556 into currency format and JavaScript statement to show output? Var input_amt = 236.2363611111556 ; mid_data = input

Explain the term- strings, Explain the term- Strings A string is genera...

Explain the term- Strings A string is generally considered to be a sequence of characters stored in memory and accessible as a unit. Strings in java are signified as objects

La Food Restaurant Program, The fancy new French restaurant La Food is very...

The fancy new French restaurant La Food is very popular for its authentic cuisine and high prices. This restaurant does not take reservations. To help improve the efficiency of the

Http 404 error /myproject/controller notfound, Running a sample Java web ap...

Running a sample Java web application from the web get http 404 error

Explain the purpose of the recovery console, Question: a) Give a detai...

Question: a) Give a detailed description of your understanding concerning "Managing User Sessions and Open files". b) What is "Overriding Inheritance" and how can it be do

How to implementing the cloneable interface, How to Implementing the Clonea...

How to Implementing the Cloneable Interface The java.lang.Object class contains a clone() method which returns a bitwise copy of the current object. protected native Object cl

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