In chapter five of the book Build Your Own Ruby on Rails Applications,
when I entered the rake db:migrate command in the Ruby console, I got
the following message back:

<code>:
Warning require_gem is obsolete. Use gem instead.
</code>

What does this mean, and what should I do? Was the rake db:migrate
command executed? If I want to update require_gem, what do I need to
do?

Thanks in advance.