SELECT sum(1) FROM (SELECT * FROM system.numbers LIMIT 1000);
SELECT sumWithOverflow(1) FROM (SELECT * FROM system.numbers LIMIT 1000);
SELECT sumKahan(1e100) - 1e100 * 1000 FROM (SELECT * FROM system.numbers LIMIT 1000);
SELECT abs(sum(1e100) - 1e100 * 1000) > 1 FROM (SELECT * FROM system.numbers LIMIT 1000);