Designing Database Tables

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    Designing Database Tables

    After learning the basic features of tables and how they are linked together to form a database, the next thing to learn is how to optimized the tables. Optimized tables are called normalized tables. In this article, I explain the use of normalized tables and give you a link to where you would learn how to produce them.

    Normal Forms
    Tables of a database are not produced arbitrarily. They have to be optimized so that they operate without ambiguity. Optimized tables are called normalized tables. Any table, whether optimized or not, can be said to be in the First Normal Form or Second Normal Form or Third Normal Form or Fourth Normal Form or "Fifth" Normal Form. The higher the Form, the more optimized is the table. In practice, a table should be in at least the third normal form. You will see the real meaning of normal forms soon.

    Deriving the Tables for a Normal Form
    One way to create the optimized tables of a database is to collect all the Input Forms (paper) and Reports of the company and derive the optimized tables from there (you will see how this is done, soon). Another way is to "break down" the structure (identify the blocks and their connections) of the company from the top and then obtain the optimized tables from the pieces (you will see how this is done, soon). Another way is to work out the optimized tables from the queries. Queries are business questions that employees of the company ask of the company while they are working (you will see details, soon).

    At the end of the series, whose link I will give you below, you will be able to produced all the optimized tables of a database.

    I said in one of the articles of this blog, that there are two types of databases: relational database and Object Database. The production of optimized tables in both database types is similar. In object databases, tables are called Classes and rows of the table are called objects.

    Use of Normalized Tables - Proper
    The production of optimized tables is done on paper. So, normalized tables are not necessarily in coded form. Even if you do not have computers in your company, you should be using normalized tables at work (in the company). Normalized tables limit the possibilities of calculation errors and also limits corruption. This is achieved by the normalized tables, by limiting inconsistencies, avoiding repetition of data, avoiding absence of data and avoiding ambiguity in general.

    The computer can not also produced correct reports if the tables are not normalized. The production of a database begins with the productions of normalized tables (at least third normal form) on paper. You can still use the computer to produced normalized tables if you have a special software for that. In my opinion you should be producing the normalized tables on paper, by hand.

    After producing the normalized tables, you do not go straight to produce the computer code for the database. You still have to take into consideration how the tables will operated in a practical computer efficiently; that is the topic for my next article in this blog. After that you can then go on to produce the computer code (you will see how this is done soon).

    I have prepared a series of tutorials on how to produced optimized (normalized) tables. I did that using a step-by-step approach. Also, the tutorials are well formatted (typed) without any special character missing. The tutorials are free. Click the following hyperlink to start the tutorials.

    Designing Database Tables