What's the best way for those who don't know C++ to help the project?

I have some experience with SQL/MySQL and could offer some help there, but I want to know how the community can help and how we can make things more efficient for the true developers working on the project. Any recommendations?

Probably looking into opened issues then try to sniff some data then build a fix after you properly tested it ideally on your local server.

There are also small changes that can do the difference like updating some coordinates / paths, spawn some missing creatures and so on.