MySql : Getting Started

Getting started with a database means first figuring out what you want to do. Our sample project in this tutorial is building a database which manages links to sites. I want to be able to add, edit and remove links in the database, as well as display links from the database. I want the links to be categorized so I can display groups of links, instead of all links at once.

I want to record the following data for each link in the database:
Name of site
URL of site
Description of site
Link Category

Each of these will become one column in a table in the database. If you are not familiar with databases, a table can be thought of somewhat as a spreadsheet in Excel. The columns in a spreadsheet relate to the columns in a database. Each row in the spreadsheet would be considered a record (or row) in the database. There also can be multiple spreadsheets in a single Excel file, as there can be multiple tables in one database.

This application could use two tables, one table to store all of the categories and another table to store all the links, with a link back to the categories table. Because this is a beginner tutorial, I keep it simple by using just one table to store the info.

Advanced Topic
Two tables is the better way to create this application. The second table would store all the category names seperately with a unique key. The unique key is just a number for each category, usually starting at 1 for the first category, 2 for the next, and so on. A record in the links table, which are the individual links, would also store this category number with the link. This number is then used to refer back to the category table to get the category name when needed. It is a little more complicated but it is a much better way to create the database.

The benefits to using multiple tables is you get faster queries, and it is easier to manage the data. Some examples of the benefits of multiple tables:
Faster query when selecting the list of all categories because you are querying a smaller set of data.
Faster queries when selecting links by category, because the it is faster to select, group and sort numbers much faster then strings.
Easier to manage because you can change the category names seperately from the links, since they only store the numbers as reference to the category name.
Easier to enter data by category because you can pull the category name from the table and display it in a select form element instead of requiring the use to type it in.

Using multiple tables (or databases) and relating their data to each other using keys is referred to as relational databases. Read more about relational database design from the related links below.