Hello,
Glad to see someone willing to do it the right way. Best advise i could give you is to learn SQL, it will help you a lot in the future to edit stored procedure and also to keep your server up. You need to understand the way it works and how SQL queries work.
It's a rather simple language, nothing to really worry about. Moreover you may need to learn PhP to create some scripts etc. (internet is full of tutorials and so on)
In my honnest opinion SQL is really the basics and what you need the most in a first time.
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