# Database theory test

• ### Question

• Hello I have database exam soon and when I'm done with it, my degree finished. Therefore, I am desperate!

Is there anyone who can fix tasks / exercises with answers in

- Normal forms
- EER modeling and SQL commands (Create Table)
- Relational Algebra
- XML Schema

Or know good sites where you learn this
Wednesday, September 28, 2011 12:58 PM

• I hate to say the obvious but can't you search the web for the questions. I mean we can propose several sites but that would be like doing something you can do yourself. If you search for example on Normalization you would get thousands of hits so why not give that a go..

Maurice
• Proposed as answer by Wednesday, February 29, 2012 7:11 AM
• Marked as answer by Monday, March 12, 2012 6:17 PM
Saturday, October 1, 2011 9:35 AM
Database normalization is a data design and organization process applied to data structures based on rules that help building relational databases. In relational database design, the process of organizing data to minimize redundancy is called normalization. Normalization usually involves dividing a database into two or more tables and defining relationships between the tables. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in just one table and then propagated through the rest of the database via the defined relationships.

Normalization : Normalization is a formal process of developing data structures in a manner that eliminates redundancy and promotes integrity.

You need to simplify structure of data in relations for easy storage and retrieval. The process of simplifying relations is called normalization.
The new relations that are obtained after normalization are called normalized relations.

Normalization has three well defined steps :
The relations that you get at the end of the first step are said to be in 1NF.
The relations that you get at the end of the second step are said to be in 2NF.
The relations that you get at the end of the third step are said to be in 3NF.
Simplifying Data to 1NF (Eliminate Repeating Groups) :
A repeating group is a set of columns that store similar info that repeats in the same table.

The constructs used in the ER model can easily be transformed into relational tables.
it is simple and easy to understand with a minimum of training. Therefore, the model can be used by the database designer to communicate the design to the end user.

• Proposed as answer by Wednesday, February 29, 2012 7:11 AM
• Marked as answer by Monday, March 12, 2012 6:17 PM
Wednesday, October 5, 2011 11:49 AM

### All replies

• I hate to say the obvious but can't you search the web for the questions. I mean we can propose several sites but that would be like doing something you can do yourself. If you search for example on Normalization you would get thousands of hits so why not give that a go..

Maurice
• Proposed as answer by Wednesday, February 29, 2012 7:11 AM
• Marked as answer by Monday, March 12, 2012 6:17 PM
Saturday, October 1, 2011 9:35 AM
Database normalization is a data design and organization process applied to data structures based on rules that help building relational databases. In relational database design, the process of organizing data to minimize redundancy is called normalization. Normalization usually involves dividing a database into two or more tables and defining relationships between the tables. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in just one table and then propagated through the rest of the database via the defined relationships.

Normalization : Normalization is a formal process of developing data structures in a manner that eliminates redundancy and promotes integrity.

You need to simplify structure of data in relations for easy storage and retrieval. The process of simplifying relations is called normalization.
The new relations that are obtained after normalization are called normalized relations.

Normalization has three well defined steps :
The relations that you get at the end of the first step are said to be in 1NF.
The relations that you get at the end of the second step are said to be in 2NF.
The relations that you get at the end of the third step are said to be in 3NF.
Simplifying Data to 1NF (Eliminate Repeating Groups) :
A repeating group is a set of columns that store similar info that repeats in the same table.

The constructs used in the ER model can easily be transformed into relational tables.
it is simple and easy to understand with a minimum of training. Therefore, the model can be used by the database designer to communicate the design to the end user.