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sql. (Note that this listing increments the database
version number, so you can still go back and run the previous examples, which have different
database structures.) Next, run the following command:
mysql -u your_mysql_username < player_schema_3.sql
Now that you have the data loaded into your database, let??™s tackle the first question.
CHAPTER 2 n CALCULATING STATISTICS WITH ACTIVE RECORD 24
Calculating Salary Distribution
You want to find how many players are at each salary rate. It??™s reasonably simple to use
Active Record??™s count function and grouping ability to calculate the distribution of the
salary, and Listing 2-2 does just that.
Listing 2-2. Calculating Salary Distribution (salary_distribution.rb)
require 'active_record'
# Establish a connection to the database. . .
ActiveRecord::Base.establish_connection(
:adapter => 'mysql',
:host => 'localhost',
:username => 'root', # This is the default username and password
:password => '', # for MySQL, but note that if you have a
# different username and password,
# you should change it.


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