517 NW 21st Ave., 503-248-6317, north45pub.com. 4 pm-midnight Monday-Thursday, 2 pm-1 am Friday, noon-1 am Saturday, 2 pm-midnight Sunday. You never know exactly what you’ll find on North 45′s rear patio, but it’s the promise of a rollicking scene tucked out of street view that keeps people waiting for a seat. But like a mullet, the party in the back is balanced by a measure of refinement. The drink list circumnavigates the globe, from renowned Belgian Trappist beers to a booklet of spirits that’s almost two dozen pages long.