Databases are very powerful as they use what we call STRUCTURED QUERY LANGUAGE. These can be used to find a record, out of many in less than milliseconds. They are an extremely powerful way of storing information, retrieving and manipulate them. Let me show you a sample of this here.

On the picture below you see three tables from a database in a store. In particular take note of the connections (black lines) between the tables. Through these connections these tables can connect with each other and hence queries can be achieved across many tables. This gives a database awsome power.

Database showing tables with relation ships

IN THIS SAMPLE THE TABLES ARE:

Categories.

This Category table includes categories of various products. There may be items such as Dairy Products, Stationaries, Fruits, Hardware and so on. If you change or add any products to it, it will automatically update the Links and Drop Down List in your office or web application.

Suppliers.

This Supplier table includes the details of each supplier. This can be very handy as each product in your database is actually pointing to your supplier.

Products.

This table contains details about your products. If you look closely, you will find that this table has relationships with other table. The Category Id points to the Category Id of the Categories table, the Suppliers Id points to the Suppliers Id table and so on. It is this relation ship between table that make databases so powerful when used with Structure Query Language.

Now you can display products by let's say the Supplier, or by Categories and so on. But you can also search for a product by any field within a table. For example we could say, give me the details of every products which costs less than $15 and is supplied by a particular supplier. The sky is the limit here as what the request may be. This requested data coming from a database can also be used to build a web page dynamically on the server and then send it to the browser who requested it. It can also by used in any other software to carry out calculations and store, print or display the results, or even to send the result to another application anywhere in the world.

Database design means that we:

1. Determine the best database to be used under the circumstances.
2. Determine the needs of the client.
3. Determine the kinds of tables and their relation ships. This includes if there is a requirement for referential integrity or not.
4. Determine the meta data of the various tables such as for example date-time, currency, varchar, nvarchar, integer, double and so on.
5. Write the necessaries SQL to run this database from an office of web application.

We have developed in Access, SQL7, SQL2000, DBISAM and in MySQL. We can also build application on an already existing database.