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You know the rudiments of the SQL query language, yet you feel you aren't taking full advantage of SQL's expressive power. You'd like to learn how to do more work with SQL inside the database before pushing data across the network to your applications. You'd like to take your SQL skills to the next level. Let's face it, SQL is a deceptively simple language to learn, and many database developers never go far beyond the simple statement: SELECT columns FROM table WHERE conditions. But there is so much more you can do with the language. In the SQL Cookbook, experienced SQL developer Anthony Molinaro shares his favorite SQL techniques and features. You'll learn about:Window functions, arguably the most significant enhancement to SQL in the past decade. I...

Understanding SQL's underlying theory is the best way to guarantee that your SQL code is correct and your database schema is robust and maintainable. On the other hand, if you're not well versed in the theory, you can fall into several traps. In SQL and Relational Theory, author C.J. Date demonstrates how you can apply relational theory directly to your use of SQL. With numerous examples and clear explanations of the reasoning behind them, you'll learn how to deal with common SQL dilemmas, such as:Should database access granted be through views instead of base tables? Nulls in your database are causing you to get wrong answers. Why? What can you do about it? Could you write an SQL query to find employees who have never been in the same department for...

The intensive search for a more secure operating system has often left everyday, production computers far behind their experimental, research cousins. Now SELinux (Security Enhanced Linux) dramatically changes this. This best-known and most respected security-related extension to Linux embodies the key advances of the security field. Better yet, SELinux is available in widespread and popular distributions of the Linux operating system--including for Debian, Fedora, Gentoo, Red Hat Enterprise Linux, and SUSE--all of it free and open source.SELinux emerged from research by the National Security Agency and implements classic strong-security measures such as role-based access controls, mandatory access controls, and fine-grained transitions and privilege...