lock

# File activerecord/lib/arel/select_manager.rb, line 54
    def lock(locking = Arel.sql("FOR UPDATE"))
      case locking
      when true
        locking = Arel.sql("FOR UPDATE")
      when Arel::Nodes::SqlLiteral
      when String
        locking = Arel.sql locking
      end

      @ast.lock = Nodes::Lock.new(locking)
      self
    end