Databases · Junior · Question 60 of 75

What does `CASE` do in a query?

SELECT name,
  CASE WHEN age < 18 THEN 'minor' ELSE 'adult' END AS group_name
FROM users;

1Creates a new table
✓Correct answer: Returns a value depending on conditions, like if/else
3Changes letter case

Explanation

It's often used inside aggregates too: COUNT(*) FILTER (WHERE ...) or SUM(CASE WHEN ... THEN 1 ELSE 0 END) to count by category.

Further reading

PostgreSQL: SELECT ↗

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