I read the O'Reilly books on Hadoop and Hvae in 2013. That was helpful, but I still think Hive is a good place to start. If you know how a join and an aggregate

I read the O'Reilly books on Hadoop and Hvae in 2013. That was helpful, but I still think Hive is a good place to start. If you know how a join and an aggregate work, you can see how Hadoop turns those into into M/R operations. If you really have to learn how Hadoop works, you'll probably have to look at the source. Write the Hello World program and get it to run on AWS EMR (as others have suggested). Then clone the source to Hadoop and open it in your favorite editor. If you have to understand the nuts and bolts, the source code is the way to go. If you only have to know how to use it, then a book + online tutorial + simple project will get you up to speed within a week or two.