MongoDb and Scaling MongoDb, two book reviews in one.

I got both books, MongoDb, The definitive guide and Scaling MongoDb last year at the MongoDB NYC conference. Somehow I forgot to write a review. Time to fix that.

The books, written by 10 gen’s employee Kristina Chodorow , are a must have for anybody working with MongoDb.

They refer to older versions of MongoDb but most of the information is still fairly relevant, so your money will be well spend.

The definitive guide teaches you everything you will need to know to get up and running with MongoDb. Installing it, querying and interacting with the database.

The second book deals with how to scale Mongo using sharding. It’s a small book that doesn’t waste your time and goes directly to the point.

MongoDb, The definitive guide

This book was written in collaboration with Michael Dirolf

<img class=“img-float-right” src=”/images/posts/mongodb-the-definitive-guide.jpg” border=“0″ alt=“MongoDb The Definitive Guide – book cover” style=“width: 30%”/>If you know what MongoDb is and why is awesome, you can skip the first chapter. If you have no idea about it go ahead and read it. It’s a short one anyway.

The “good stuff” really starts on the second chapter with a good overview of documents, collections, dbs, the mongo shell and data types.

Chapter 3 goes on and build on that, showing the multiple ways you have to insert and update data.

Once you have data in the system you will learn on chapter 4 how to read it. Of course, you want to do that really fast so the next chapter deals with indexing.
There is a good section on how to use the “explain” and “hint” commands to tune up your indexes.

You will see two examples on using MapReduce in chapter 6 and some aggregation.

Chapter 7 deals with some more advanced topics like using capped collection (for example for logs) and GridFS to store files.

For sharding, I will recommend getting the second book in this review.

The next three chapters will help you with administration, replication and sharding.

The administration chapter is certainly very good.

The book ends with four example applications written in Java, PHP, Ruby and Python.

Scaling MongoDb

<img class=“img-float-right” src=”/images/posts/scaling-mongodb.jpg” border=“0″ alt=“MongoDb The Definitive Guide – book cover” style=“width: 30%”/>It’s a very small book at just 49 pages, but packed with information.
Starts with a quick explanation of sharding and quickly move on unto how to split the data and balance load.

Chapter 3 is probably the highly of the book giving you different strategies on choosing the all important shard key, sharding collections, adding and removing capacity.

There is a bit of a discussion on what makes for a good shard key, what to avoid and what are the problems when choosing what it looks like a good key but is not.

In the next chapter, the author show how to work with collections and indexes. There is only a paragraph on Map Reduce in this book and relate to the behaviour of map reduce in sharded scenarios.

The last chapter (almost) deals with administering the shard. Again very valuable information on how on what to check for, working with outages and a few ideas on how to prevent them.

There is a sixth chapter but is just one page with further reading material. I feel that should be call Appendix instead.

Conclusions

As I mentioned before you should definitely buy both these books and read them in order, starting with the definitive guide.