You will review some of the most commonly used SQL commands to ensure you are prepared to tackle both real-world problems as well as every exercise covered in this course.

Essential SQL

Review the essentials

Practice the essentials

Transforming your results

Transform numeric & strings

Extract what you need

Working with aggregate functions

Aggregating finances

Aggregating strings

Which tables?

Use Real-World SQL

How do you find the data you need in your database in order to answer real-world business questions?  Here you will learn how to use system tables to explore your database. You will use these tables to create a new tool that contains a list of all tables and columns in your database. Finally, you will create an Entity Relationship Diagram (ERD) which will help you connect multiple tables.

Find the right table

LIMITing your search

Which table to use?

What tables are in your database?

Determine the monthly income

Join the correct tables

What columns are in your database?

A VIEW of all your columns

Testing out your new VIEW

The average length of films by category

Complex joins

Build the entity relationship diagram

Which films are most frequently rented?

Find Your Data

Working with SQL to solve real-world problems will oftentimes require you to do more than retrieve the data you need, oftentimes you will need to manage the data in your database. This includes creating data, updating it and, when necessary, deleting it.

Store your data

Storing new data

Using existing data

TABLE vs VIEW

Update your data

What should you modify?

Update the price of rentals

Updated based on other tables

Delete your data

Deleting all table data

Delete selected records

A family friendly video store

Manage Your Data

How do you ensure that the SQL scripts you write will be easy to understand for anyone who needs to read them? This chapter will cover approaches you can leverage to ensure that your code clearly conveys your intent, is readable by others and follows best practices.

Convey your intent

How to convey our intent

Clarify the intent of this query

Fix this query - intent

Write readable code

How to make code easier to read

Make this query easier to read - Part I

Make this query easier to read - Part II

Avoid common mistakes

What are the don'ts of writing SQL code?

Apply best practices to your code

Recap

Best Practices for Writing SQL

DVD Rental Database

Now that you’ve learned the basic tools of SQL you are ready to synthesize them into practical, real-world skills. In this course, you will work with a database of a fictional movie rental company. The size and complexity of this database will allow you to experience the challenges of working with databases firsthand. Throughout this course, you will use SQL to answer business-driven questions. You will learn new skills that will empower you to find the tables you need. You will then learn how to store and manage this data in tables and views that you create. Best of all you will also learn how to write code that not only clearly conveys your intent but is also legible.

Data Manipulation in SQL

Find tables, store and manage new tables and views, and write maintainable SQL code to answer business questions.

Applying SQL to Real-World Problems

SQL para analistas de negócios

Lead Data Scientist, Memorial Sloan Kettering Cancer Center

DROP, TRUNCATE, DELETE

DELETE inactive customers

DELETE using a subquery

Let's DELETE some records!

https://s3.amazonaws.com/assets.datacamp.com/production/course_14822/subtitles/course_14822_5d3d3b2b2d84352b1bed7193e5db2ef6.vtt

Manage Your Data - Delete your data

Delete your data

Create Your Free Account