Filtering results using the WHERE Clause and the IN operator.

By Alan Hylands — 1 minute read

Tidying up our WHERE clause with IN.

You can see from the previous OR operator example how your WHERE clause could get a little unwieldy after a while when using multiple different conditions.

If we were also specifying date ranges, upper and lower price limits, types of holiday, number of passengers etc. as well it could become VERY untidy to read and maintain.

We can do a little housekeeping to protect against that in our IDE by using brackets and liberal use of tabs. To tidy up the multiple OR conditions themselves we could also use the IN statement.

E.g.

SELECT * 
FROM holidays 
WHERE Country IN ('Spain','Portugal','Greece');

The Question.

Let's tidy up the query from the last lesson. Use the IN keyword to bring back the same results i.e. everyone who has black OR brown hair.

The Data.

Table Name: characters

id	name	gender	hair
1	Thor	Male	Blond
2	The Wasp	Female	Brown
3	Jessica Jones	Female	Black
4	Hawkeye	Male	Brown

The Editor.

Run SQL

Show Answer

The Answer.

Correct SQL:

                    SELECT * FROM characters WHERE hair IN ('Black','Brown');

Correct Output:

Try the next lesson