instead of this
UPDATE staff SET salary = 1200 WHERE name = 'Bob';
UPDATE staff SET salary = 1200 WHERE name = 'Jane';
UPDATE staff SET salary = 1200 WHERE name = 'Frank';
UPDATE staff SET salary = 1200 WHERE name = 'Susan';
UPDATE staff SET salary = 1200 WHERE name = 'John';
you can use
UPDATE staff SET salary = 1200 WHERE name IN ('Bob', 'Frank', 'John');