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.

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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

Creating indexes on all columns is a bad idea.

Blindly declaring indexes on all columns of a table is a bad idea most of the time, for the following reasons:
1. An index takes up disk space. More indexes mean higher disk space usage, potentially reaching the limit of the underlying operating system's storage.

2. Write queries including inserts, updates, and deletes.

Creating indexes on all columns is a bad idea.
Blindly declaring indexes on all columns of a table is a bad idea most of the time, for the following reasons:
<ol>
<li>
An index takes up disk space. More indexes mean higher disk space usage, potentially reaching the limit of the underlying operating system’s storage.
</li>
<li>
Write queries including inserts, updates, and deletes.
</li>
</ol>

Tim just joined your team and noticed the home page load time was very slow. He figured that the SQL query that returned data to the front end was running slowly. He determined the fix to create indexes on all the columns of the table. As a senior member of the team, why or why not do you think his solution is right?

Tim just joined your team and noticed the home page load time was very slow. He figured that the SQL query that returned data to the front end was running slowly. He determined the fix to create indexes on all the columns of the table. As a senior member of the team, why or why not do you think his solution is right?

Question # 1

Question # 1

Quiz yourself on index and join operations in MySQL.

Introduction

Basic SQL

Joins

Nested Queries

Multi Table Operations

Views

Stored Procedures

Triggers

Miscellaneous

Practice & Prep

Epilogue

Quiz 3