Why is the usual 'paste' not very handy? It's what it's meant for. Suggestions:
Write yourself an unusual paste function that does what you want. Maybe you just don't like typing 'sep=""' all the time. So write a function that calls paste with sep="". Or whatever.
Building long SQL queries with string concatenation is potential fail anyway. See http://xkcd.com/327/ for the canonical example.
Another possibility is some kind of templating solution. I've used the brew package in the past and it's great for that.
