This book explains the inner workings of an Oracle database. I appreciated the writing style and the depth of the material. The one piece that I didn't appreciate was when the other Oracle products were introduced (Designer, Developer, Forms, etc.) They read like advertisements, without any serious evaluation. I would have liked to have seen whether they would be useful to a given reader. An example would be: Oracle Designer requires 2 person-years to set up the default properties (a company I used to work for paid quite a bit to get a set of working defaults).