Question

我有

Year : 2011
Month: Nov
Day: Sun
WeekNumber(Monthwise): 4

欲望输出：

Date
--------
2011-11-20

如何在单个SQL语句中执行此操作？

由于

Answer 1

我可能会考虑使用NEXT_DAY函数返回工作日的第一天，前提是在给定日期之后发生。一旦你有了这个，你就可以添加所需的周数。

这方面的一个例子可能是：

with test_data as (
  select
    '2011' as the_year,
    'Nov' as the_month,
    'Sun' as the_day,
    4 as the_week
  from dual
)
select 
  the_year, the_month, the_day, the_week,
  next_day(to_date(the_year||the_month, 'YYYYMON') - 1, the_day) + 
    7* (the_week -1) as the_date
from test_data

Answer 2

这可能有用。

SELECT NEXT_DAY( TO_DATE(TO_CHAR((4-1)*7) || '-' || 'NOV' || '-' || '2011','dd-mon-yyyy') ,'Sun') 
FROM DUAL

请参阅：http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/functions093.htm

Answer 3

尝试：

SELECT A.B + B.D YourDate 
FROM (SELECT TO_DATE (Your4DigitYear || LPAD ( YourMonth, 2, '0' ) || LPAD ( DECODE (YourWeekOfMonth, 1, '1', (YourWeekOfMonth - 1) * 7 ), 2, '0' ), 'YYYYMMDD') B FROM DUAL) A, (SELECT LEVEL - 1 D FROM DUAL CONNECT BY LEVEL < 15) B WHERE 
TO_CHAR (A.B + B.D, 'D' ) = YourDayOfWeek AND 
TO_CHAR (A.B + B.D, 'W' ) = YourWeekOfMonth;

给出年，月，日和月的明智周数，我该如何找到日期？

3 个答案: