当前月份的一周-间隔

Question

如何从当前月份每隔1./2./3./4-5周(间隔)选择一次？

所以不像：

select to_char(sysdate,'W') from dual

但我需要一个间隔=当月的一周(例如，oktober的2周，因为现在是10月- sysdate)。因此，具体而言：

select SUM(number)/((trunc(sysdate,'WW')/4) from my_table where date between ? and ? 

Answer 1

像这样的东西应该对你有用。

SELECT TO_CHAR(datecol,'W') AS week, 
       SUM(countcol) AS sum_of_sales
FROM sales
  WHERE TO_CHAR(datecol,'YYYYMM') = TO_CHAR(SYSDATE,'YYYYMM') --current year and month.
  GROUP BY TO_CHAR(datecol,'W')
ORDER BY TO_CHAR(datecol,'W')