Question

我是否可以找到特定月份的星期六和星期日的某一天的日期例如，考虑2017年1月的月份。以下日期是周末

7/1/2017 - Saturday

14/1/2017 - Saturday

21/1/2017 - Saturday

28/1/2017 - Saturday

1/1/2017 - Sunday

8/1/2017 - Sunday

15/1/2017 - Sunday

22/1/2017 - Sunday

29/1/2017 - Sunday

我想要SQL查询，这样当我将月份和年份作为输入时，它应该给我上述所有日期（只有星期六和星期日的日期）作为输出

Answer 1

SQL查询中的简单调整可以为您提供所需的输出。希望这会有所帮助。

SELECT A.DT,
  TO_CHAR(A.DT,'FmDay') DAY
FROM
  (SELECT TRUNC(sysdate,'MONTH')+level DT
  FROM DUAL
    CONNECT BY level <= TO_CHAR(LAST_DAY(sysdate),'fmDD')
  )a
WHERE TO_CHAR(a.dt,'FmDAY') IN ('SATURDAY','SUNDAY');

Answer 2

试试这个。在第4行，您可以将年/月组合。我以2017-02为例。

SELECT TRUNC(dt, 'MM') + LEVEL - 1 AS mdate
,to_char(TRUNC(dt, 'MM') + LEVEL - 1,'DY' ) as m_day
FROM 
(select to_date('2017-02','YYYY-MM') as dt from dual) --this is where you can put year/month
where to_char(TRUNC(dt, 'MM') + LEVEL - 1,'DY' ) in ('SAT','SUN')
CONNECT BY TRUNC(TRUNC(dt, 'MM') + LEVEL - 1, 'MM') = TRUNC(dt, 'MM')

输出

MDATE       M_DAY 
04-FEB-2017 SAT
05-FEB-2017 SUN
11-FEB-2017 SAT
12-FEB-2017 SUN
18-FEB-2017 SAT
19-FEB-2017 SUN
25-FEB-2017 SAT
26-FEB-2017 SUN

Answer 3

我将对代码进行一些重大更改我们可以获得一年中所有的周日和周六

SELECT TRUNC(dt, 'yyyy') + LEVEL - 1 AS mdate
,to_char(TRUNC(dt, 'yyyy') + LEVEL - 1,'DY' ) as m_day
FROM
(select to_date('2020-01','YYYY-MM') as dt from dual) --this is where you can put year/month
where to_char(TRUNC(dt, 'yyyy') + LEVEL - 1,'DY' ) in ('SAT','SUN')
CONNECT BY TRUNC(TRUNC(dt, 'yyyy') + LEVEL - 1, 'yyyy') = TRUNC(dt, 'yyyy')

如何获取特定星期六或一个月的星期日的日期

3 个答案: