Bag om SQL
SQL, pronounced ess-que-el, is a domain-specific language; this means that it is made for a certain purpose. Unlike general purpose languages like C++ or Ruby, SQL was made for a singular purpose, and to be excellent at that one purpose. It's similar to the way HTML is designed to make web pages, and it falls into the same niche as MUCH soft code.While alternatives to SQL like ISAM or VSAM exist, they have largely faded out of use due to SQL's superiority. SQL is the pioneer of accessing N records with a singular command, and generally works without indexing, which means there's no need to designate the method by which to reach a record.SQL encompasses pretty much anything you can think of doing with a database, ranging from querying data, to manipulating and defining it. Due to its scope, many people, and even professionals insist on describing SQL as a declarative language. While this is generally true, SQL also incorporates many procedural elements. In this book, we don't want to teach you the basics of SQL. The parts of SQL you should have learned at school are of no interest to us. We'll be looking at more advanced forms of SQL, those that your boss would give you a pat on the back for, and probably consider you a programming genius for.Naturally, we'll guide you step-by-step through this process. When it comes to learning advanced SQL, you'll find that much of it is not simply about learning commands like SET or GROUP BY, but that most of it is purely related to your mindset. How well you can understand programming concept, how well you can truly learn to think like a database.So start learning to be a master of SQL and grab this book to start your journey!
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