Depends where you are and what kinda boat you've got. If you've got about 2" of the stern out of the water like I do....anchor it bow out.
At BR, I generally just grab a buoy that nobody's using....if it belongs to someone and they need it...I'll gladly move. If it's not packed, I just tie off the bow and let the boat dangle downriver. If it's packed, I get a stern line.
I've used anchors like you posted up in the river with a decent current, you just gotta drop it right then pull it a bit to set it in the bottom.