How to COUNT rows when they have a COUNT in them

[Dave Torr]

Probably simple but I can't figure it out!

THe manual section 3.3.4.8 has the example

SELECT owner, COUNT(*) FROM pet GROUP BY owner

which is fine. Now what I want to do is count the number of rows this 
returns. Actually of course this is trivial - I can just count how many 
owners there are.

What I actually have is something similar to

SELECT owner, COUNT(*) as c FROM pet GROUP BY owner HAVING c>1

(ie I want to see the owners who have more than one pet). And I just want to 
know how many there are - at the moment I am having to retreive the full 
data set (which is large in my case).

What I want is something like

SELECT COUNT(SELECT owner, COUNT(*) FROM pet GROUP BY owner HAVING c>1)

but that doesn't work....