Introduction to Databases for the Web: Pt. 1

It is important to note that for most databases, you will actually need to log on. That is, most databases implement a security system that gives various users different privileges to do different things such as READ ONLY or READ/WRITE.

Most likely, your database administrator will have provided you with a login name and a password. She will also have either provided you with the net address of the database so you can log in remotely, or has given you a direct command line shell.

Once you are logged in to a database, you can begin to populate the database with data or extract already existing data. Let's look first at populating the database.

A Sample Database

Okay, let's define a simple relational database that we can use to practice with...

We will define a database called "MY_COMPANY" with four tables, "CLIENTS", "EMPLOYEES", "PRODUCTS", and "SALES". These tables will look something like the following: