Working with data 7

W

ORKING WITH DATA

If you are using CocoaMySQL, go to the  Query  tab. If you are using the command line,

make sure you are in the mysql command line, and remember to end your statements with

semicolons.

From this point on, I'm assuming that you have access to a MySQL database and that your

username and password have been set up to let you work on that database.

Connect

If you are not connected to your MySQL server, connect to your server the same way you

did earlier.

Change password

It is a good idea to change your password regularly. Usually, your initial password is sent to

you by way of e mail. E mail is notoriously insecure, so it is always a good idea to change

your password as soon as you connect the first time.

set password = old_password(`

NEWPASSWORD

')

Choose database

In CocoaMySQL, you'll choose your database from the pull down menu in the upper left.

On the command line, you'll choose your database by typing  use 

DATABASENAME

;  and

pressing the return key on your keyboard.

Choose the  music  database.

About Tables and Columns

All of your data in MySQL is stored in tables. When you view tables, they look a lot like

spreadsheets. Each table consists of rows and columns. A row is one record; it is one set of

data. A column is a field: it is one piece of data that each record has.

For example, if you are keeping a database of your record albums, you will have a row for

Alice Cooper's  Brutal Planet . You will have a column for the artist's name ( Alice Cooper )

and the album name ( Brutal Planet ).

Basic field types

In MySQL, you must specify what kind of data will go into columns. The two field types

you'll use most often are probably varchar and int. These are strings or text, and numbers.

The title of an album and the artist is an example of text. If you also keep track of the year

that the album came out, this is a number.

With varchar, you need to specify the maximum size of the text. If you specify a size that is

too  low,  extra  text  will  be  truncated.  You  can  always  go  back  and  change  your  mind,

however.