近30天

-- 近30天
SELECT to_char(day,'yyyy-mm-dd') as "days"
          from (
        SELECT to_date(to_char(trunc(to_date('2021-09-30','yyyy-MM-dd'), 'dd'), 'yyyy-mm-dd'), 'yyyy-mm-dd') - rownum + 1 as day
          FROM dual
                  CONNECT BY ROWNUM <= 30
        )
ORDER BY day asc

近5年

-- 近5年
SELECT to_char(SYSDATE,'YYYY') - LEVEL + 1 as "xAxisValue"
FROM dual
CONNECT BY LEVEL <= 5
ORDER BY to_char(SYSDATE,'YYYY') - LEVEL + 1 ASC

近6个月

-- 根据当前时间获取最近6个月时间(yyyy-mm)：
SELECT
TO_CHAR(add_months(to_date(to_char(trunc(sysdate, 'mm')+1, 'yyyy-mm'), 'yyyy-mm'), -(ROWNUM - 1)), 'yyyy-mm') as "xAxisValue"
FROM dual
  CONNECT BY ROWNUM  <= 6
  ORDER BY TO_CHAR(add_months(to_date(to_char(trunc(sysdate, 'mm')+1, 'yyyy-mm'), 'yyyy-mm'), -(ROWNUM - 1)), 'yyyy-mm') ASC

日期区间的天数

SELECT to_char(day, 'yyyy-mm-dd') as "xAxisValue"
from (
         SELECT to_date(to_char(trunc(to_date('2021-07-10', 'yyyy-mm-dd'), 'dd'), 'yyyy-mm-dd'), 'yyyy-mm-dd') -
                rownum + 1 as day
         FROM dual
         CONNECT BY ROWNUM <= (to_date('2021-07-10', 'yyyy-mm-dd') - to_date('2021-06-10', 'yyyy-mm-dd') + 1)
     )
ORDER BY day asc