Since CHL's are state-by-state their is no national database on them. Their is no US "clearing house" of concealed carry holders. In Oregon, a police agency cannot see if you have a CHL from another state, however it maybe logged in a Criminal History Report, as a non-criminal finger print submission. I'd have to check on that. Also, I don't know if Canada has access to the same reports as LEO's in the US do.
Exactly. The CBSA does have access to your criminal arrest history that is how they can deny you entry for a DUI you had in the 1970s.. this was opened up after 911. After 911, lots of businessmen who used to travel up here were being turned around because they had never had their DUI expunged from their records.