What is a "low level caching" in Rails in terms of SQL Caching?

In the Rails Guides about caching there is an explanation:

However, it’s important to note that query caches are created at the
start of an action and destroyed at the end of that action and thus
persist only for the duration of the action. If you’d like to store
query results in a more persistent fashion, you can in Rails by using
low level caching.

So what is that “low level caching”? Is it explained in Guides?

On Tuesday, June 4, 2013 10:33:49 AM UTC-4, Ruby-Forum.com User wrote:


Posted via http://www.ruby-forum.com/.

Actually, I don’t think it is. It might be and I’m just not aware of
it.
Rails has several layers of caching. Page, Action, and fragment
caching
are high level caches. There’s a general cache, Rails.cache, that
exists
and you can write to it directly at a lower level. Typically, this is
done
in a model and the mainstay of low level caching is the
Rails.cache.fetch
method. You can also initiate your own caches. There might be places
on
the web that document it. It’s pretty well documented in The Rails 4
Way
but
that’s a book you would need to purchase.

check this article out.
http://robotmay.com/post/23161612605/everyone-should-be-using-low-level-caching?20dba200

i hope you find it useful