We'll be utilizing DB Fiddle to practice SQL in this study guide.
What's DB Fiddle? It's an "SQL Database Playground", think of it like a sandbox environment. You can create, read, update, and delete information from a database without consequences.
Here's what DB Fiddle looks like:
In the "Schema SQL" box to the left, we need to place an SQL script that'll create our database, tables, and records.
I've already pre-made that script for you. Download the ZIP file containing it by clicking here. Copy and paste the entire contents of the "Northwinds SQL Script" text file from the folder to the Schema SQL box. To do this, click anywhere in the file and then press Ctrl + A (Mac users: Cmd + A)
Your page should look like this as a result:
Now, whenever we want to run a query on the database, we can place the query in the "Query SQL" box to the right on DB Fiddle and then press "Run" in the top left corner. For example...
SELECT *
FROM suppliers;
This is how you'll run each query for all the following questions. Always place your queries in the "Query SQL" box.