As far as the syntax is concerned SQL is pretty darn easy. I was able to get simple programs (java+SQL with mySQL DB) to work on the first day of learning (I was new to java and new to SQL, but knew C++ very well). Designing a database properly is a whole different story. It looks very easy at the beginning, but the deeper you get into it, you better understand how complex it is. If you start today and spend all your time reading books on databases and writing your own DB apps, you should be ready to do it professionally by the end of june.
I develop web pages in vim.
Can't tell you anything about php.