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Views are virtual tables. That means they should be updatable, just as "real" or base tables are. In fact, view updatability isn't just desirable, it's crucial, for practical reasons as well as theoretical ones. But view updating has always been a controversial topic. Ever since the relational model first appeared, there has been widespread skepticism as to whether (in general) view updating is even possible. In stark contrast to this conventional wisdom, this book shows how views, just like base tables, can always be updated (so long as the updates don't violate any integrity constraints). More generally, it shows how updating always ought to work, regardless of whether the target is a base table or a view. The proposed scheme is 100% cons...

What makes Windows refugees decide to get a Mac? Enthusiastic friends? The Apple Stores? Great-looking laptops? A "halo effect" from the popularity of iPhones and iPads? The absence of viruses and spyware? The freedom to run Windows on a Mac? In any case, there's never been a better time to switch to OS X-and there's never been a better, more authoritative book to help you do it. The important stuff you need to know: Transfer your stuff. Moving files from a PC to a Mac by cable, network, or disk is the easy part. But how do you extract your email, address book, calendar, Web bookmarks, buddy list, desktop pictures, and MP3 files? Now you'll know. Recreate your software suite. Many of the PC programs you've been using are Windows-only. Disc...

You can do many things with NOOK HD right out of the box, but if you really want to get the most from your HD or HD+ tablet, start with this book. With clear instructions, full-color illustrations, and savvy advice from technology expert Preston Gralla, you'll learn how to use email and the Web, watch movies and shows, play games, listen to music, and enjoy your personal ebook library. The important stuff you need to know: Relax with a book. Load your NOOK library with ebooks, comics, and interactive books for kids. Play with apps. Enjoy the games and apps everyone's talking about. Go online. Browse the Web and check your email with built-in WiFi. Be social. Share books and recommendations with your NOOK Friends, and Facebook and Twitter contacts. Ta...