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4. Active Record
gem "activerecord", "8.1.4"; gem "activesupport", "8.1.4"; gem "sqlite3", "2.9.6"
require "active_record"
require "active_record/connection_adapters/sqlite3_adapter"
ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
ActiveRecord::Base.connection.execute(<<~SQL)
CREATE TABLE users (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, age INTEGER)
SQL
class User < ActiveRecord::Base
end
User.create!(name: "alice", age: 30)
User.create!(name: "bob", age: 25)
User.create!(name: "carol", age: 35)
puts User.count
p User.where(name: "bob").pluck(:id, :name, :age)
p User.where("age > ?", 26
u = User.find(1)
puts "#{u.id} #{u.name} #{
p User.find_by(name: "nobody")
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