Oracle SQL如果有时不存在，该如何选择（或包含数据）？

Question

当我在视图中选择数据时， 在大多数情况下，我将获得数据：

Referred Job_Status     Jobs
OPS      DISPATCHED     9
OPS      NOT_DISPATCHED 3

但是有时候数据不存在，我只能得到这个：

Referred Job_Status     Jobs
OPS      DISPATCHED     9

当它不存在时，我仍然想将其显示为零：

Referred Job_Status     Jobs
OPS      DISPATCHED     9  
OPS      NOT_DISPATCHED 0

对不起，我有一个星期五早上，我无法直截了当。

Answer 1

您可以尝试以下操作：

with main as (
select 'OPS' Referred ,'DISPATCHED' Job_Status FROM DUAL
UNION
select 'OPS' Referred ,'NOT_DISPATCHED ' Job_Status FROM DUAL
)
SELECT
MAIN.Referred ,MAIN.Job_Status , NVL(SUB.JOBS,0) JOBS
FROM MAIN LEFT OUTER JOIN YOUR_VIEW SUB ON  MAIN.REFERRED=SUB .REFERRED 
                                        AND MAIN.Job_Status =SUB.Job_Status ;