比较一系列月份中的月份并在 oracle 中获得下一个更高的月份

Question

换个说法，我在一列中有一个字符串，其月份为“3-6-9-12”。我必须通过比较字符串中的月份和提取（sysdate 中的月份）来获得下一个处理月份。 例如，五月的月份是 5 ，所以我希望字符串中的下个月是 6 。 七月份是 7 月份，所以我应该在下个月得到 9 月份。如果可能的话，我想在一个内联查询中做到这一点。 我正在尝试使用此查询来获取下个月 -

select instr(x,extract(month from sysdate))+1 from (select listagg(to_number(regexp_substr((extract(month from sysdate)||'-3-6-2-12'), '[^-]+', 1 ,level)),'-') 组内 (按 to_number(regexp_substr((extract(month from sysdate)||'-3-6-2-12'), '[^-]+', 1 ,level)))x 从 dual 排序 connect by regexp_substr((extract(month from sysdate)||'-3-6-2-12'), '[^-]+', 1 ,level) is not null order by to_number(x))

如果有其他更好的方法可以在 sql 中查找下个月，请提供帮助。

Answer 1

你可以做一个月份和季度的映射，然后选择季度

     with date_mapping as(select 1 month,3 quater from dual union all
                         select 2 month,3 quater from dual union all
                         select 3 month,3 quater from dual union all
                         select 4 month,6 quater from dual union all
                         select 5 month,6 quater from dual union all
                         select 6 month,6 quater from dual union all
                         select 7 month,9 quater from dual union all
                         select 8 month,9 quater from dual union all
                         select 9 month,9 quater from dual union all
                         select 10 month,12 quater from dual union all
                         select 11 month,12 quater from dual union all
                         select 12 month,12 quater from dual),
     data as (select   date '2020-12-01' date1 from dual)
     select ds.quater from data dd ,date_mapping ds
     where extract (month from dd.date1)=ds.month

如果您的 Quater 未修复，您可以使用以下内容

WITH quaters
 AS (SELECT to_number(Regexp_substr(quaters, '[^-]+', 1, LEVEL)) quater
     FROM   (SELECT ( '1-4-7-10' ) AS quaters
             FROM   dual)
     CONNECT BY LEVEL <= Regexp_count(quaters, '[^-]+')),
 min_max_quater
 AS (SELECT Max(quater) max_quater,
            Min(quater) min_quater
     FROM   quaters),
 date_mapping
 AS (SELECT lvl         month,
            Min(quater) quater
     FROM   dual,
            quaters
            cross join (SELECT LEVEL lvl
                        FROM   dual
                        CONNECT BY LEVEL < = 12)
     WHERE  lvl <= quater
     and lvl <> quater
     GROUP  BY lvl
     UNION ALL
     SELECT LEVEL month,
            min_quater
     FROM   min_max_quater
     WHERE  LEVEL > max_quater
     CONNECT BY LEVEL <= 12
     UNION ALL
     SELECT max_quater,
            min_quater
            FROM 
        min_max_quater
     )
  SELECT ds.quater
   FROM   dual dd,
   date_mapping ds
  WHERE  Extract (month FROM sysdate) = ds.month