SUM

일반적인 예

SELECT 
  SUM(point) as point

IF를 사용한 예

SELECT 
  SUM( IF(point > 0, point, 0)) as point

CASE 를 사용한 예

SELECT 
SUM( CASE WHEN (item = \'deposit\') THEN point ELSE 0 END) as deposits,
SUM( CASE WHEN (item = \'withdrawal\') OR (item = \'fiat\') THEN point ELSE 0 END) as withdrawals'),