Text values go inside single quotes

A piece of text in SQL is called a string, and a string is written inside single quotes: 'Lisbon'. The quotes tell the database this is text, not the name of a column. Numbers need no quotes. Write the string exactly as it is stored, capital letters and all — some databases treat 'lisbon' and 'Lisbon' as different values.

SELECT name
FROM students
WHERE city = 'Lisbon';