gistfile2.sh

% sequel sqlite://test.db

gistfile3.rb

# count
> DB[:items].count
=> 2

# select all
> DB[:items].all
=> [{:price=>100.0, :name=>"foo", :id=>1}, {:price=>200.0, :name=>"bar", :id=>2}]

# select first
> DB[:items].first
=> {:price=>100.0, :name=>"foo", :id=>1}

# select id = 2
> DB[:items][:id => 2]
=> {:price=>200.0, :name=>"bar", :id=>2}

# select price = 200
> DB[:items].filter(:price => 200).all
=> [{:price=>200.0, :name=>"bar", :id=>2}]

# select price > 100
> DB[:items].filter{|i| i.price > 100}.all
=> [{:price=>200.0, :name=>"bar", :id=>2}]

# select price < 100
> DB[:items].filter('price < ?', 200).all
=> [{:price=>100.0, :name=>"foo", :id=>1}]

test.rb

require 'rubygems'
require 'sequel'

DB = Sequel.sqlite('test.db')

DB.create_table :items do
  primary_key :id
  String :name
  Float :price
end

items = DB[:items]
items << {:name => 'foo', :price => 100}
items << {:name => 'bar', :price => 200}