Rails - Aug 2006 - duplicate entry mystery

I have a rails app that has a sync feature which looks up a remote database and
updates the local database accordingly. Anyway, things work great for the most
part, but there is a section of code which seems to randomly raise errors. I
have something like this: 

   homelinks = Syncinventorydesc.find(:all)

   InventoryDescription.delete_all()

   for link in homelinks

     locallink = InventoryDescription.new()

     locallink.inventory_id = link.inventory_id
     locallink.description_id = link.description_id

     locallink.save!
   end

this code tears down the local table completely before going through each item
fetched on the remote db and inserting them in. Every now and then i get the
duplicate error message (there a no duplicate keys in the original table), which
suggests that either not all records are getting wiped out of the local table OR
a record is getting saved twice somehow.. both seem very unlikely.

i have wrapped the locallink.save! in a rescue block to let the exception slide
which should silence this problem, but the mystery remains. Anybody know
what''s
up? Thanks

Stuart


Thanks