This book was not edited for content, grammar, or style. Half of the chapters are not composed of complete sentences. The examples in all chapters do not correspond to the text, for example showing a query that took 57 seconds while the text claims it took 19 minutes. Some of the content, where phrased in the form of a sentence and using the correct words, is nonetheless incorrect. And despite being titled "PostgreSQL 9.6 ..", this was written before 9.1 was released and has not been updated for any more recent versions.
