دانلود کتاب راهنمای جیبی SQL

nce the last edition of SQL Pocket Guide was published, a lot has changed in the data world. The amount of data generated and collected has exploded, and a number of tools and jobs have been created to handle the influx of data. Through all of the changes, SQL has remained an integral part of the data landscape. Over the past 15 years, I have worked as an engineer, consultant, analyst, and data scientist, and I have used SQL in every one of my roles. Even if my main responsibilities were focused on another tool or skill, I had to know SQL in order to access data at a company. If there was a programming language award for best supporting actor, SQL would take home the prize. As new technologies emerge, SQL is still top of mind when it comes to working with data. Cloud-based storage solutions like Amazon Redshift and Google BigQuery require users to write SQL queries to pull data. Distributed data processing frameworks like Hadoop and Spark have sidekicks Hive and Spark SQL, respectively, which provide SQL-like interfaces for users to analyze data. SQL has been around for almost five decades, and it is not going away anytime soon. It is one of the oldest programming languages still being used widely today, and I am excited to share the latest and greatest with you in this book. There are many existing SQL books out there, ranging from ones that teach beginners how to code in SQL to detailed technical specifications for database administrators. This book is not intended to cover all SQL concepts in depth, but rather to be a simple reference for when: • You’ve forgotten some SQL syntax and need to look it up quickly • You’ve come across a slightly different set of database tools at a new job and need to look up the nuanced differences • You’ve been focusing on another coding language for a while and need a quick refresher on how SQL works If SQL plays a large supporting role in your job, then this is the perfect pocket guide for you.