■■高手救命！字段是Date类型，值是2002/05/05,我要传入某个日期数据例如2002/10/30,在SQL语句中如何求差几天？？？

Question

date('2002/05/05','yyyymmdd')-date('2002/10/30','yyyymmdd')

Answer 1

两个日期直接相减
或
trunc(date1-date2)

Answer 2

abs(trunc(date1-date2))//只求相差天数，无正负

Answer 3

SQL> select to_date('2002/05/05','yyyy/mm/dd')-to_date('2002/10/30','yyyy/mm/dd') from dual;TO_DATE('2002/05/05','YYYY/MM/DD')-TO_DATE('2002/10/30','YYYY/MM/DD')
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                                                                 -178SQL> select abs(to_date('2002/05/05','yyyy/mm/dd')-to_date('2002/10/30','yyyy/mm/dd')) from dual;ABS(TO_DATE('2002/05/05','YYYY/MM/DD')-TO_DATE('2002/10/30','YYYY/MM/DD'))
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