path: root/activerecord/test/cases/adapters/mysql/explain_test.rb

require "cases/helper"
require 'models/developer'
require 'models/computer'

class MysqlExplainTest < ActiveRecord::MysqlTestCase
  fixtures :developers

  def test_explain_for_one_query
    explain = Developer.where(id: 1).explain
    assert_match %(EXPLAIN for: SELECT `developers`.* FROM `developers` WHERE `developers`.`id` = 1), explain
    assert_match %r(developers |.* const), explain
  end

  def test_explain_with_eager_loading
    explain = Developer.where(id: 1).includes(:audit_logs).explain
    assert_match %(EXPLAIN for: SELECT `developers`.* FROM `developers` WHERE `developers`.`id` = 1), explain
    assert_match %r(developers |.* const), explain
    assert_match %(EXPLAIN for: SELECT `audit_logs`.* FROM `audit_logs` WHERE `audit_logs`.`developer_id` = 1), explain
    assert_match %r(audit_logs |.* ALL), explain
  end
end