Ruby script to see the DDL ran by rails in a migration

README.md

Place this in the rails root of your project. And then call

ruby rails_migration_checker.rb <path/to/migration 1> [<path/to/migration 2>...]

rails_migration_checker.rb

#!/usr/bin/env ruby

module Wrapper
  def execute(sql, *args)
    puts "  > " + sql.gsub(/`/, '') + ";"
    super
  end
end

require_relative 'config/environment'

ActiveRecord::Base.connection
ActiveRecord::Migration.verbose = false
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.prepend(Wrapper)

queue = []

while path = ARGV.shift
    require_relative path
    filename = File.basename(path, ".rb")
    timestamp, name = filename.split("_", 2)
    name = name.camelcase
    migration = name.constantize

    schema_change = ActiveRecord::SchemaMigration.new(:version => timestamp.to_s)

    queue.append([
        migration,
        name,
        timestamp,
        schema_change,
    ])
end

puts
puts "======  UP  ======="
queue.each do |(migration, name, timestamp, schema_change)|
    puts "^ #{timestamp}_#{name}"
    migration.migrate(:up)
    schema_change.save
end

puts
puts "====== DOWN ======="
queue.reverse_each do |(migration, name, timestamp, schema_change)|
    puts "v #{timestamp}_#{name}"
    migration.migrate(:down)
    schema_change.destroy
end