زبان اس کیو ال؛ چگونگی دسترسی به داده ها در پایگاه های داده رابطه‌ای

Most SQL texts attempt to serve as an encyclopedic reference on SQL syntax - an approach that is counterproductive, since this information is readily available in online references published by the major database vendors. For SQL beginners, it's more important for a book to focus on general concepts and offer clear explanations and examples of what the various statements can accomplish. This is that beginner book. A number of features make The LANGUAGE OF SQL unique among introductory SQL books. First, you will not be required to download software or sit with a computer as you read the text. The intent of this book is to provide examples of SQL usage that can be understood simply by reading them. Second, topics are organized in an intuitive and logical sequence. SQL keywords are introduced one at a time, allowing you to build on your prior understanding as you encounter new words and concepts. Finally, this book covers the syntax of three widely used databases: Microsoft SQL Server, MySQL, and Oracle, with special "Database Differences" boxes that will show you any differences in the syntax among those three databases, as well as instructions on how to obtain and install free versions of the databases. This is the only book you'll need to gain a working knowledge of SQL and relational databases.