Exercise: Scalar Functions

rim whitespace and uppercase every artist name. Show artist_id, the original name, and the cleaned name aliased as cleaned. Order by artist_id.

Round each payment's amount up to the next whole number using CEIL. Show payment_id, amount, and the result aliased as rounded_up. Order by payment_id.

Build a display label for each artist that combines the trimmed, uppercased name with the country in parentheses. Skip artists whose country is NULL. Show artist_id and the result aliased as label. Order by artist_id.

Extract each user's email domain and count how many users share each domain. Show domain and the count aliased as user_count. Order by user_count descending, then domain ascending.

Return only tracks whose track_id is even. Show track_id, title, and duration_seconds. Order by track_id.

Find payments where the amount differs from the refund amount, and return the absolute difference. Show payment_id, amount, refund_amount, and the absolute difference aliased as diff. Order by diff descending, then payment_id ascending.