甲骨文子查询错误

Question

select SELLS.BEER, SELLS.PRICE, SELLS.BAR 
from FREQUENTS 
where FREQUENTS.DRINKER = 'Sally' 
    and FREQUENTS.BAR IN (select SELLS.BAR from SELLS where PRICE > 5); 

以下是错误消息：

ORA-00904: "SELLS"."BAR": invalid identifier 
00904. 00000 - "%s: invalid identifier" 
*Cause:  
*Action: 
Error at Line: 43 Column: 33 

我已签表中的所有列，他们看起来适合我，但是我找不到。

有人可以告诉我错误在哪里吗？我正在尝试解决它，而不使用JOIN。

Answer 1

这可能工作：

select s.BEER, s.PRICE, s.BAR 
from FREQUENTS, SELLS s 
where FREQUENTS.DRINKER = 'Sally' AND FREQUENTS.BAR IN (select SELLS.BAR from SELLS where PRICE > 5); 

如果我得到你的逻辑，试试这个：

select s.BEER, s.PRICE, s.BAR 
from FREQUENTS, SELLS s 
where FREQUENTS.DRINKER = 'Sally' AND FREQUENTS.BAR IN (select SELLS.BAR from SELLS where s.PRICE > 5); 

Answer 2

SELLS没有被连接到主查询等什么你选择是无效的。

SELECT s.BEER, s.PRICE, s.BAR 
FROM FREQUENTS f 
INNER JOIN SELLS s ON f.BAR = s.BAR 
WHERE f.DRINKER = 'Sally' 
AND f.BAR IN (SELECT sa.BAR 
       FROM SELLS sa 
       WHERE sa.PRICE > 5); 

甚至可能更简单：

SELECT s.BEER, s.PRICE, s.BAR 
FROM FREQUENTS f 
INNER JOIN SELLS s ON f.BAR = s.BAR 
WHERE f.DRINKER = 'Sally' 
AND s.PRICE > 5; 

没有连接：

SELECT s.BEER, s.PRICE, s.BAR 
FROM SELLS s 
WHERE s.BAR = (SELECT f.BAR 
       FROM FREQUENTS f 
       WHERE f.DRINKER = 'Sally') 
AND s.PRICE > 5;