HANA SQL获取当前月的第一天

SELECT ADD_DAYS(CURRENT_DATE,-EXTRACT(DAY FROM CURRENT_DATE) + 1) FROM DUMMY; 


SELECT ADD_MONTHS(NEXT_DAY(LAST_DAY(CURRENT_DATE)),-1) FROM DUMMY;

SELECT ADD_DAYS(LAST_DAY(ADD_MONTHS(CURRENT_DATE,-1)),1) FROM DUMMY;SELECT ADD_DAYS(CURRENT_DATE,-EXTRACT(DAY FROM