I agree there are always trade-offs, but at least as far as "losing a lot of he database performance" and "doing complex joins on your front end", I don't think there is anything in the PostgREST approach that would push in that direction. For more background on the performance part (Oracle-specific but most of it carries over) check out http://www.prohuddle.com/webinars/ToonKoppelaars/ThickDB.php