內聯視圖中的 ORA-1427

Question

我們的 Prod 環境中有一個查詢失敗，該查詢因 ora-01427 單行子查詢返回更多行而失敗。 這是 oracle 11g 數據庫。 如下查詢。 這個查詢運行良好，直到我們用 SQ3 添加最后的左外連接，一旦添加它會在一段時間后失敗並出現 ORA-1427。

select c1,c2..c8 from
t1 left join
(subquery with joins)SQ1
left join
(subquery with joins)SQ2
left join
(subquery with joins)SQ4
left join
(subquery with joins)SQ5
left join
(SELECT DISTINCT MAX(c1) c1, c2, c3, c4, c5,c6 
     FROM s1.t1 WHERE  c2='NY' AND c7<'2' AND c8='Y' 
GROUP BY c1, c2, c3, c4, c5,c6) SQ3 ON sq3.c3=t1.c3
                                                 AND sq3.c8=t1.c8
                                                  AND sq3.c7=t2.c6
                                                  AND sq3.c6 <'2'
                                                AND sq3.c4='Y' 

當我使用 WITH 子句重寫此查詢時，它運行良好，見下文。 當下面的第二個執行沒有改變邏輯時，為什么第一個查詢失敗的任何想法。

with
(SELECT DISTINCT MAX(c1) c1, c2, c3, c4, c5,c6 
     FROM s1.t1 WHERE  c2='NY' AND c7<'2' AND c8='Y' 
GROUP BY c1, c2, c3, c4, c5,c6) as SQ3
select c1,c2..c8 from
t1 left join
(subquery with joins)SQ1
left join
(subquery with joins)SQ2
left join
(subquery with joins)SQ4
left join
(subquery with joins)SQ5
left join
 SQ3 ON sq3.c3=t1.c3
 AND sq3.c8=t1.c8
 AND sq3.c7=t2.c6
 AND sq3.c6 <'2'
 AND sq3.c4='Y' 

Answer 1

Mira a ver esto de agrupar por la columna del agregado, no parece correcto (SELECT DISTINCT MAX(c1) c1 , c2, c3, c4, c5,c6 FROM s1.t1 WHERE c2='NY' AND c7<'2' AND c8='Y' **

按c1 分組

**

Answer 2

您不需要按與聚合 function 一起使用的列進行分組。 因此，將您的最后一個查詢更改為 -

SELECT MAX(c1) c1, c2, c3, c4, c5,c6 
  FROM s1.t1
 WHERE c2 = 'NY'
   AND c7 < '2'
   AND c8 = 'Y' 
 GROUP BY c2, c3, c4, c5,c6