您可以使用布尔逻辑来描述您的条件，而不是 case 表达式：

(terms = 'First Quarter'  and months in ('JAN', 'FEB', 'MAR'))
or (terms = 'Second Quarter' and months in ('APR', 'MAY', 'JUN'))
or (terms = 'First Half'     and months in ('JAN', 'FEB', 'MAR', 'APR', 'MAY', 'JUN'))

这可以缩短一点：

(terms in ('First Quarter',  'First Half') and months in ('JAN', 'FEB', 'MAR'))
or (terms in ('Second Quarter', 'First Half') and months in ('APR', 'MAY', 'JUN'))

这里有一个选择；第1-8行的样本数据。您可能感兴趣的查询从第9行开始。取决于你用什么工具， '&&terms' 可能看起来与此不同（例如。 :terms ). 这是sql*plus。而且，我用缩写代替了你的“四分之一”之类的东西（我不想打那么多）。

SQL> with months (mon, num) as
  2  (select 'jan', 1 from dual union all
  3   select 'feb', 2 from dual union all
  4   select 'mar', 3 from dual union all
  5   select 'apr', 4 from dual union all
  6   select 'may', 5 from dual union all
  7   select 'jun', 6 from dual
  8  )
  9  select *
 10  from months
 11  where mon in
 12    (select *
 13       from table(sys.odcivarchar2list('jan', 'feb', 'mar'))
 14       where '&&terms' = 'FQ'
 15     union all
 16     select *
 17       from table(sys.odcivarchar2list('apr', 'may', 'jun'))
 18       where '&&terms' = 'SQ'
 19     union all
 20     select *
 21       from table(sys.odcivarchar2list('jan', 'feb', 'mar', 'apr', 'may', 'jun'))
 22       where '&&terms' = 'FH'
 23    )
 24 order by num;
Enter value for terms: SQ
MON        NUM
--- ----------
apr          4
may          5
jun          6

--

SQL> undefine terms
SQL> /
Enter value for terms: FH
MON        NUM
--- ----------
jan          1
feb          2
mar          3
apr          4
may          5
jun          6
6 rows selected.
SQL>