04 Combine conditions

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Goal

List the name and price of every product in the Books or Games category that costs less than 20.

AND needs both sides to be true; OR needs either. IN ('a', 'b') is a tidy way of writing several ORs on one column.

Mixing them is where people slip. AND binds tighter than OR, so category = 'Books' OR category = 'Games' AND price < 20 means "all Books, plus cheap Games" — not what you meant. Use IN, or brackets: (category = 'Books' OR category = 'Games') AND price < 20.

Try it

Cheap books and games only. Try the version without brackets first and compare.

Go to the terminal

Hint

WHERE category IN ('Books', 'Games') AND price < 20.

Show a solution

SELECT name, price FROM products WHERE category IN ('Books', 'Games') AND price < 20;

This interactive environment needs JavaScript. Everything you need to read is on this page, and the solution works the same way for real.

SQL

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