PostgreSQL 9.0 High Performance: today's free (highly-rated) e-book

Hope this offer from PacktPub gets in front of a few more eyes; this is the only one of their books I've paid for! (Back when it was on sale for $5 - https://news.ycombinator.com/item?id=6933716 )

one of the rare good PacktPub books https://news.ycombinator.com/item?id=10808912

bottom-up, structured approaches to benchmarking low-level system performance https://news.ycombinator.com/item?id=3797082

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A great book on query plan stuff https://news.ycombinator.com/item?id=9823263

This book is phenomenal. https://news.ycombinator.com/item?id=2597774

a few of the best I'm aware of https://news.ycombinator.com/item?id=5699248

Amazon 4.7 stars with 13 reviews http://amzn.com/dp/B0057G9RUG