您可以有一个已经完成的带有月份的表，然后“加入”它，按日期分组，或者您可以使用子查询或使用 with 语句创建一个，例如
WITH Months (month) AS (
SELECT 1 AS Month FROM DUAL
UNION ALL
SELECT MONTH + 1
FROM Months
WHERE MONTH < 12
)
SELECT *
FROM Months
LEFT JOIN SomeTable
ON SomeTable.month = Months.MONTH
--ON Extract(MONTH FROM SomeTable.date) = Months.MONTH
编辑
一个更好的例子：
--Just to simulate some table data
WITH SomeData AS (
SELECT TO_DATE('01/01/2019', 'MM/DD/YYYY') AS Dat, 5 AS Value FROM dual
UNION ALL
SELECT TO_DATE('01/05/2019', 'MM/DD/YYYY') AS Dat, 7 AS Value FROM dual
UNION ALL
SELECT TO_DATE('03/03/2019', 'MM/DD/YYYY') AS Dat, 2 AS Value FROM dual
UNION ALL
SELECT TO_DATE('11/05/2019', 'MM/DD/YYYY') AS Dat, 9 AS Value FROM dual
)
, Months (StartDate, MaxYear) AS (
SELECT CAST(TO_DATE('01/01/2019', 'MM/DD/YYYY') AS DATE) AS StartDate, 2019 AS MaxYear FROM DUAL
UNION ALL
SELECT CAST(ADD_MONTHS(StartDate, 1) AS DATE), MaxYear
FROM Months
WHERE EXTRACT(YEAR FROM ADD_MONTHS(StartDate, 1)) <= MaxYear
)
SELECT
Months.StartDate AS Dat
, SUM(SomeData.Value) AS SumValue
FROM Months
LEFT JOIN SomeData
ON Extract(MONTH FROM SomeData.Dat) = Extract(MONTH FROM Months.StartDate)
GROUP BY
Months.StartDate
编辑
您不会找到只是复制过去的解决方案，您需要从中获取想法并更改您的上下文。
让我们试试这个。您可以在APP中“添加”缺少的月份，或者您可以将它与已经完成的表格一起加入，不需要是真正的表格，您可以制作一张。 with 语句就是一个例子。因此，让我们在 2019 年的最后一天获得整个月：
--Geting the last day of every month for 2019
WITH Months (CurrentMonth, MaxYear) AS (
SELECT CAST(TO_DATE('01/01/2019', 'MM/DD/YYYY') AS DATE) AS CurrentMonth, 2019 AS MaxYear FROM DUAL
UNION ALL
SELECT CAST(ADD_MONTHS(CurrentMonth, 1) AS DATE), MaxYear
FROM Months
WHERE EXTRACT(YEAR FROM ADD_MONTHS(CurrentMonth, 1)) <= MaxYear
)
SELECT LAST_DAY(Months.CurrentMonth) AS LastDay
FROM Months
好的，现在我们所有月份都可以加入。在您的查询中，您已经完成了总和，因此让我们跳过总和并使用您的数据。只需添加另一个 with 查询。
--Geting the last day of every month for 2018
WITH Months (CurrentMonth, MaxYear) AS (
SELECT CAST(TO_DATE('01/01/2018', 'MM/DD/YYYY') AS DATE) AS CurrentMonth, 2018 AS MaxYear FROM DUAL
UNION ALL
SELECT CAST(ADD_MONTHS(CurrentMonth, 1) AS DATE), MaxYear
FROM Months
WHERE EXTRACT(YEAR FROM ADD_MONTHS(CurrentMonth, 1)) <= MaxYear
)
, YourData as (
SELECT sl.loonperiode_dt, (sum(slr.uren)) code_220
FROM HR.soc_loonbrief_regels slr,
HR.soc_loonbrieven sl,
HR.werknemers w,
HR.v_kontrakten vk
WHERE sl.loonperiode_dt BETWEEN '01012018' AND '01122018'
AND slr.loon_code_id IN (394)
AND slr.loonbrief_id = sl.loonbrief_id
AND w.werknemer_id = sl.werknemer_id
AND w.werknemer_id = vk.werknemer_id
AND vk.functie_id IN (121, 122, 128)
AND sl.loonperiode_dt BETWEEN hist_start_dt AND last_day(nvl(hist_eind_dt, sl.loonperiode_dt))
AND w.afdeling_id like '961'
GROUP BY sl.loonperiode_dt
--ORDER BY sl.loonperiode_dt
)
SELECT
LAST_DAY(Months.CurrentMonth) AS LastDay
, COALESCE(YourData.code_220, 0) AS code_220
FROM Months
Left Join YourData
on Extract(MONTH FROM Months.CurrentMonth) = Extract(MONTH FROM YourData.loonperiode_dt)
--If you have more years: AND Extract(YEAR FROM Months.CurrentMonth) = Extract(YEAR FROM YourData.loonperiode_dt)
ORDER BY LastDay ASC