How do I learn #SQL for #data analysis?
Step 1:
This is a good starting point: SQL School Table of Contents
OR, this: Learn SQL
Both of these resources were put together by analytics vendor and is targeted towards beginners.
Step 2:
Review this Quora Thread: How do I learn SQL?
Participate in competitions like this: Solve SQL Code Challenges
Step 3:
If you like to go more in-depth then check out few books:
Head First SQL
Learn SQL the hard Way
Certification books/material from a database vendor
Hope that helps!