generally speaking, you cannot pass a link identifier across pages reliably. I.e. you can't be gauranteed to get the same link, and often, the link has been "reset" so it looks clean and new.
If you want to pass session data across pages, just pass the row id of whatever row you were accessing on the previous page to the next.
persistant connects are a performance enhancer, but can cause MASSIVE problems on an improperly configured (for persistant connects) apache/php/database server.