Books are nice. Besides reading them they are also a nice decoration on your shelf. There is a brilliant TED talk by Chip Kidd on this subject.
But sometimes books have drawbacks. This is where I have to start the comparison with vinyl records (Yes, you're still reading a database oriented blog). Vinyl records look nice and are still being sold and yes I also still use them. The drawback is that car dealers start to look puzzeled if you ask them if your new multimedia system in your car is able to play your old Led Zeppelin records. The market for portable record players is small, and that's for a good reason.
The problem with books about databases is that they get old very soon. The MySQL 5.1 Cluster Certification Study Guide was printed by lulu.com which made it possible to quickly update the material. This made sure that the material wasn't outdated when you bought it.
I like to use books as reference material, but I tend to use Google more often and the books stay on the bookshelf and are getting old and dusty. One of the reasons for this is that taking books with me just for reference is not an option judging by the weight of it.
At Percona Live UK I got a voucher from O'reilly to get a free e-Book. So I chose 'SQL and Relational Theory'. I started to read it on my laptop with FBreader and on my iPhone using Stanza. Both my phone and laptop are not really made for reading. So I bought an Sony Reader, which is made for reading.
Reading 'SQL and Relational Theory' on the Sony Reader is nice. The only annoyance is that the examples are like this:
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