Gain insights into SQL by exploring database creation, data manipulation, and advanced queries. Learn about practical applications and practice for SQL interviews to build confidence and readiness.

sql.tar.gz

The ability to work SQL is becoming an increasingly in-demand skill, both for software developers and people in less technical roles. If you’re interested in learning SQL and have no prior experience with it, then this course will be your light in a dark tunnel.

You’ll start by covering the basics of SQL such as how to create a database, how to insert, query, and update data. You’ll also learn fundamental concepts that developers and data scientists use everyday such as multi-table operations, nested queries, and how to set up views. 

Throughout, you’ll get to execute SQL queries in your browser and see results in real-time - you won’t need to worry about set-up.

At the end of this course, you’ll also get some hands-on practice with common SQL interview questions, so when the time comes, you’ll be ready and confident to answer any question that comes your way. Let’s get started!

An Introductory Guide to SQL

In this lesson we'll learn about the boolean operator __EXISTS__ and its complement, __NOT EXISTS__. The __EXISTS__ operator is usually used to test if a subquery returns any rows or none at all.


>Connect to the terminal below by clicking in the widget. Once connected, the command line prompt will show up. Enter or copy and paste the command **./DataJek/Lessons/33lesson.sh** and wait for the MySQL prompt to start-up.

This lesson discusses the EXISTS operator.

Introduction

Basic SQL

Joins

Nested Queries

Multi Table Operations

Views

Stored Procedures

Triggers

Miscellaneous

Practice & Prep

Epilogue

EXISTS Operator