Has_many finder_sql #{id} single/double quotes voodoo

I never would have figured this out in many moons:

has_many :subscribers, :class_name => “Person”,
:finder_sql =>
'SELECT DISTINCT people.* ’ +
'FROM people p, post_subscriptions ps ’ +
'WHERE ps.post_id = #{id} AND ps.person_id =
p.id ’ +
‘ORDER BY p.first_name’

Variable interpolation in single quotes? Putting it
in double quotes results in a really high number
(541239078 vs. 15 in my case). Is this explained
somewhere?

csn


Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around