Introduction
Very simple subqueries
Subqueries with multiple results
Correlated subqueries
Instruction
Excellent! These examples are getting too easy for you! Let's try something more complicated.
So far, our subqueries only returned single values (like 5 or 15.28 for example). Let's change that.
First, we need to learn a new operator. Take a look at the example:
SELECT * FROM city WHERE rating IN (3, 4, 5);
Can you guess what IN means? That's right, it allows you to specify a few values in the WHERE clause instead of just one.
In our example, we only want to show interesting cities, but we're not very picky – any city with a rating 3 OR 4 OR 5 will do. That's what IN (3,4,5) means.
Exercise
Find all information about hiking trips with difficulty 1, 2, or 3.
Stuck? Here's a hint!
Type:
SELECT * FROM hiking_trip WHERE difficulty IN (1,2,3);
