A Gentle Introduction to SQL Queries

Link: A Gentle Introduction to SQL Queries: "In this tutorial we will learn about the concepts behind the SQL syntax. We will go through the basics of how to use the FROM and WHERE clauses, and move on to more advanced topics like joins, aggregations and subqueries. If you’re anything like me, SQL is one of those things that may look easy at first (it reads just like regular english!), but for some reason you can’t help but google the correct syntax for almost every query."

Linked is a handy little SQL tutorial and guide.