SQL (Structured Query Language) is one of the most important skills for us, data people. So in this article + video, get the necessary SQL skills you need for Data Analysis work.
Step 0: Install MySQL software
I am using the FREE MySQL Community Edition software to learn & practice SQL at home. You can get it from here.
If you have any other database software available (such as SQL Server or Oracle), you can use them to follow this tutorial.
Step 1: Import Awesome Chocolates Dataset
You need some data to practice SQL. So I prepared a sample dataset for a fictional (but yummy) company called Awesome Chocolates.
After you have the file,
- Open MySQL Workbench, login if necessary
- Click on the “server administration” tab (see illustration, click to expand)
- Click on “Data Import/Restore”
- Select the option “Import from self-contained file”
- Specify the path of the downloaded awesome-chocolates-data.sql file
- Start import
At the end of these steps, your MySQL should have the awesome chocolates database. Congratulations 🎉🥳
You can see this from “Schemas” tab on the workbench
Using SQL Server?
You can also use SQL Server to practice SQL. If you are using SQL Server Management Console, then follow below steps to import the data.
- Download this SQL Server Backup file
- Unzip the file
- Open SSMS & right click on the databases and chose “Restore Database” option. Follow the steps on that screen using below screenshots.
Step 2: Learn SQL for Data Analysis with this video
Everything is ready. Time to learn SQL.
I made an hour long tutorial to explain all the necessary SQL concepts for you. In this video, you will learn:
- How to use SELECT statement to answer business questions
- Working with WHERE clause
- Using AND, OR, NOT and combining them to create complex queries.
- Sorting query results using ORDER BY
- Combining data from two or more tables using JOINS
- Creating reports with GROUP BY
- More than 50 example queries, tips and ideas
Please watch the video below or on my YouTube Channel.
Here are some of the example queries covered in the video lesson. Feel free to copy paste them in to SQL console to see how they work.
-- Select everything from sales table select * from sales; -- Show just a few columns from sales table select SaleDate, Amount, Customers from sales; select Amount, Customers, GeoID from sales; -- Adding a calculated column with SQL Select SaleDate, Amount, Boxes, Amount / boxes from sales; -- Naming a field with AS in SQL Select SaleDate, Amount, Boxes, Amount / boxes as 'Amount per box' from sales; -- Using WHERE Clause in SQL select * from sales where amount > 10000; -- Showing sales data where amount is greater than 10,000 by descending order select * from sales where amount > 10000 order by amount desc; -- Showing sales data where geography is g1 by product ID & -- descending order of amounts select * from sales where geoid='g1' order by PID, Amount desc; -- Working with dates in SQL Select * from sales where amount > 10000 and SaleDate >= '2022-01-01'; -- Using year() function to select all data in a specific year select SaleDate, Amount from sales where amount > 10000 and year(SaleDate) = 2022 order by amount desc; -- BETWEEN condition in SQL with < & > operators select * from sales where boxes >0 and boxes <=50; -- Using the between operator in SQL select * from sales where boxes between 0 and 50; -- Using weekday() function in SQL select SaleDate, Amount, Boxes, weekday(SaleDate) as 'Day of week' from sales where weekday(SaleDate) = 4; -- Working with People table select * from people; -- OR operator in SQL select * from people where team = 'Delish' or team = 'Jucies'; -- IN operator in SQL select * from people where team in ('Delish','Jucies'); -- LIKE operator in SQL select * from people where salesperson like 'B%'; select * from people where salesperson like '%B%'; select * from sales; -- Using CASE to create branching logic in SQL select SaleDate, Amount, case when amount < 1000 then 'Under 1k' when amount < 5000 then 'Under 5k' when amount < 10000 then 'Under 10k' else '10k or more' end as 'Amount category' from sales; -- GROUP BY in SQL select team, count(*) from people group by team
SQL Practice Problems
Once you understand the concepts I’ve demoed in the video, try to solve below homework problems.
If you want to cheat, use the solutions tab to see the answers.
👉 You need to combine various concepts covered in the video to solve these
1. Print details of shipments (sales) where amounts are > 2,000 and boxes are <100?
2. How many shipments (sales) each of the sales persons had in the month of January 2022?
3. Which product sells more boxes? Milk Bars or Eclairs?
4. Which product sold more boxes in the first 7 days of February 2022? Milk Bars or Eclairs?
5. Which shipments had under 100 customers & under 100 boxes? Did any of them occur on Wednesday?
👉 These require concepts not covered in the video
1. What are the names of salespersons who had at least one shipment (sale) in the first 7 days of January 2022?
2. Which salespersons did not make any shipments in the first 7 days of January 2022?
3. How many times we shipped more than 1,000 boxes in each month?
4. Did we ship at least one box of ‘After Nines’ to ‘New Zealand’ on all the months?
5. India or Australia? Who buys more chocolate boxes on a monthly basis?
Resources to Learn More
SQL is a great skill to have if you work with data. Please use below courses, books, articles & websites to learn more.
If you use my links to purchase the books or courses, I get a small affiliate commission.
There is no extra cost to you, obviously.
All the best 👍
I wish you all the best with your SQL learning. Do let me know in the comments below if you have enjoyed this article and the video.