我编写了一个查询,以使用sysdate获取当前年度和上一年季度的开始日期。
例如今天是一年的第一季度,因此我只想获取去年和今年第一季度的开始日期。 如果我在12月(第4季度),我想获得8个季度的开始日期(去年为4个季度,今年为4个)。
select b.dt,
to_number(to_char(SYSDATE, 'Q')),
to_number(to_char(b.dt, 'Q'))
from dual a,
(select add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE, 'MM'), -12),
'yyyy'),
(rownum - 1) * 3) dt
from all_objects
where rownum <= 8
and add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE, 'MM'), -12),
'yyyy'),
(rownum - 1) * 3) <= SYSDATE
and to_number(to_char(SYSDATE, 'Q')) >=
to_number(to_char(add_months(trunc(ADD_MONTHS(TRUNC(SYSDATE,
'MM'),
-12),
'yyyy'),
(rownum - 1) * 3),
'Q'))) b
此查询仅返回去年第一季度的开始日期。我预计也将获得今年第一季度的开始日期。
答案 0 :(得分:2)
这是一个选择;查看代码中的注释。
SQL> alter session set nls_date_format = 'dd.mm.yyyy';
Session altered.
SQL> with
2 -- this mimics SYSDATE
3 today (datum) as
4 (select date '&date_literal' from dual),
5 -- which quarter does DATUM belong to? Find 1st day in "this" and "previous" year
6 quart as
7 (select trunc(datum, 'yyyy') this,
8 trunc(add_months(datum, -12), 'yyyy') previous,
9 to_char(datum, 'q') quart from today)
10 -- the fina result
11 select add_months(this, (level - 1) * 3) result
12 from quart
13 connect by level <= quart
14 union all
15 select add_months(previous, (level - 1) * 3) result
16 from quart
17 connect by level <= quart;
Enter value for date_literal: 2019-03-24
RESULT
----------
01.01.2019
01.01.2018
SQL> /
Enter value for date_literal: 2019-08-13
RESULT
----------
01.01.2019
01.04.2019
01.07.2019
01.01.2018
01.04.2018
01.07.2018
6 rows selected.
SQL>