Ruby MySQL Tutorial

This brief Ruby MySQL Tutorial shows you how you can connect to MySQL in Ruby. MySQL support in Ruby was made possible by Tomita Masahiro. He has developed a pure Ruby binding called Ruby/MySQL. We need to install the same on our PC and the installation (you need to be connected to the internet and it takes some time) is as shown below:

C:\>gem install mysql
Bulk updating Gem source index for: http://gems.rubyforge.org
Select which gem to install for your platform (i386-mswin32)

 1. mysql 2.7.1 (mswin32)

 2. mysql 2.7 (ruby)

 3. mysql 2.6 (ruby)

 4. mysql 2.5.1 (ruby)

 5. Cancel installation

> 1
Successfully installed mysql-2.7.1-mswin32
Installing ri documentation for mysql-2.7.1-mswin32...
Installing RDoc documentation for mysql-2.7.1-mswin32...
C:\>

This installs mysql-2.7.1-mswin32 driver which is faster and supports MySQL 4.1 and later. The documentation for this driver is here.

I will assume that you’ve already installed mySQL 4.1 or above on your PC and that you have it running and are familiar with the basics.

Now, run the mysql client program from the command line, as:

C:\>mysql

You should get the mysql prompt. Next, create a database ruby as:

mysql> create database ruby;
Query OK, 1 row affected (0.02 sec)

Next, create a table student in the database ruby as:

mysql> use ruby;
create table student (id VARCHAR(2), name VARCHAR(20), rank VARCHAR(2));

As a first exercise we try to connect to the MySQL server and print all the names in the table student. Program p078rubymysql.rb

require 'mysql'

#my = Mysql.new(hostname, username, password, databasename)
con = Mysql.new('localhost', '', '', 'student')
rs = con.query('select * from student')
rs.each_hash { |h| puts h['name']}
con.close

It is as simple as that. You can explore this api further.