leaderboard self hosting ifs and hows

Hi Unity,

after being totally frustrated with Baas solutions like Gamesparks, App42, etc because of their unreasonable pricing (don't try to convince me otherwise), I decided to make my leaderboards from scratch. So I am turning to the community for a torch on my way. My first question is should I use NoSQL or SQL database for the leader boards? What are significant difference in terms of leaderboard implementations? Do I Are there any ready made libraries I can use or I should implement everything from scratch and yes I already found this link: http://gamedevelopment.tutsplus.com/tutorials/how-to-code-a-self-hosted-phpsql-leaderboard-for-your-game--gamedev-11627 This would be my choice if nobody chips in for any help I guess.

PS: I don't like the idea of freemium games, I firmly believe that they destroy the user experience. And if you get paid per download(opt out of in-app purchases), Baas is not a good solution. Just in case you were wondering why I don't use Baas for the game.