* 성능 개선율 : (튜닝 전 - 튜닝 후) / 튜닝 후 [ 튜닝 전 ] 아래 쿼리를 살펴보도록 하겠습니다. SELECT CNT1, CNT2, CNT3, CNT4, CNT5, CNT6, CNT7, CNT8 FROM ( SELECT (SELECT COUNT(*) FROM CHG_LOGS WHERE REG_DT=:B1 AND ST_CD='0' AND LOG_LVL='1') CNT1 , (SELECT COUNT(*) FROM CHG_LOGS WHERE REG_DT=:B1 AND ST_CD='1' AND LOG_LVL='1') CNT2 , (SELECT COUNT(*) FROM CHG_LOGS WHERE REG_DT=:B1 AND ST_CD='2' AND LOG_LVL='1') CNT3 , (SELECT COU..