加入后无效的标识符

Question

任何人都可以解释为什么我收到以下错误消息：

  

ORA-00904：＆＃34; BPT＆＃34;。＆＃34; OBA_REQ_FK＆＃34;：无效标识符

sql可以正常工作，直到我把它放在我的连接中。

left outer join (Select *
From (SELECT OBA_REQ_FK, Max(CRE_DATE) AS CRE_DATE
FROM fmis.open_burn_requests_pt
GROUP BY OBA_REQ_FK) ptl
join 
(SELECT OBA_REQ_FK, USNG_COORDS,CRE_DATE
FROM fmis.open_burn_requests_pt) ttl
on ttl.CRE_DATE = ptl.CRE_DATE) bpt on bpt.oba_req_fk = oba.pk  

Answer 1

问题在于子查询SELECT *。

子查询上有两个列名ptl.oba_req_fk和ttl.oba_req_fk，外ON不知道要使用哪一个

你需要确定你需要哪一个。

LEFT OUTER JOIN 
( 
       SELECT  -- * ptl.oba_req_fk,ttl.oba_req_fk
       FROM   ( 
                       SELECT   oba_req_fk, 
                                max(cre_date) AS cre_date 
                       FROM     fmis.open_burn_requests_pt 
                       GROUP BY oba_req_fk) ptl 
       JOIN 
              ( 
                     SELECT oba_req_fk, 
                            usng_coords, 
                            cre_date 
                     FROM   fmis.open_burn_requests_pt) ttl 
       ON     ttl.cre_date = ptl.cre_date
) bpt ON bpt.oba_req_fk = oba.pk

注意：

1. 避免使用select *请select您需要的列这可以提高性能
2. 如果要在表上选择相同的列名，可以使用别名。

修改

我想你需要获得ptl.oba_req_fk，因为你想获得最后的日期数据。

LEFT OUTER JOIN 
( 
       SELECT  ptl.oba_req_fk,
               ptl.cre_date,
               ttl.usng_coords
       FROM   ( 
                       SELECT   oba_req_fk, 
                                max(cre_date) AS cre_date 
                       FROM     fmis.open_burn_requests_pt 
                       GROUP BY oba_req_fk) ptl 
       JOIN 
              ( 
                     SELECT oba_req_fk, 
                            usng_coords, 
                            cre_date 
                     FROM   fmis.open_burn_requests_pt) ttl 
       ON     ttl.cre_date = ptl.cre_date
) bpt ON bpt.oba_req_fk = oba.pk

Answer 2

好的，这就是我所做的，现在似乎可行了：

left outer join (Select *
From (SELECT OBA_REQ_FK, Max(CRE_DATE) AS CRE_DATE
FROM fmis.open_burn_requests_pt
GROUP BY OBA_REQ_FK) ptl
join 
(SELECT OBA_REQ_FK as OBAREQFK, USNG_COORDS,CRE_DATE
FROM fmis.open_burn_requests_pt) ttl
on ttl.CRE_DATE = ptl.CRE_DATE) bpt on bpt.oba_req_fk = oba.pk