I have a problem to sum of field that always show null, I already tried all of these MySQL query,
(SUM(IFNULL(topup_amount,0))) AS total,
SUM(topup_amount) AS total2,
COALESCE(SUM(topup_amount),110),
IFNULL(SUM(topup_amount), 0),
COALESCE(SUM(topup_amount), 0)
But always show null result, I need 0 (zero) result. Anyone know about this?