無效使用組運行的同時使用GROUP BY

Question

select a.col_name1,max(b.col_name2) from table_a , table_b b where 
a.candidate_id = 900 and a.col_name1 = b.col_name1 and a.col_name2= 
    302885 group by b.candidate_id; 

這是查詢工作正常，我

但是當我使用MAX（b.col_name2）它給這個錯誤1111 invalid use of group function。

select a.col_name1,max(b.col_name2) from table_a , table_b b where 
a.candidate_id = 900 and a.col_name1 = b.col_name1 and a.col_name2= 
max(b.col_name2)group by b.candidate_id; 

如何使用max(b.col_name2)值

提前請幫me.Thanks ..

Answer 1

試試這個

select a.col_name1,max(b.col_name2) 
    from table_a , table_b b 
    where a.candidate_id = 900 
    and a.col_name1 = b.col_name1 
    group by b.candidate_id 
    having a.col_name2= max(b.col_name2) 

或

select a.col_name1,max(b.col_name2) 
    from table_a , table_b b 
    where a.candidate_id = 900 
    and a.col_name1 = b.col_name1 
    and a.col_name2 in (select max(col_name2) from table_b) 
    group by b.candidate_id 

Answer 2

當USI NG組通過你需要指定組的WHERE子句HAVING子句中：

select a.col_name1, 
    max(b.col_name2) 
from table_a , table_b b 
where a.candidate_id = 900 and 
    a.col_name1 = b.col_name1 
group by b.candidate_id 
having a.col_name2 = max(b.col_name2) 

Answer 3

僅僅因爲你的查詢運行並不意味着它「效果很好。」

Mysql有一些奇怪的分組功能。

試試這個：

select 
    a.col_name1, 
    max(b.col_name2) 
from table_a 
join table_b b 
    on a.col_name1 = b.col_name1 
where a.candidate_id = 900 
and a.col_name1 = b.col_name1 
and a.col_name2 = 302885 
group by a.col_name1; 

修正/改進：

• 格式化
• 按列

Answer 4

而且，總是用明確的JOIN語法聯接語法

組。 ..

SELECT a.col_name1 
    , MAX(b.col_name2) 
    FROM table_a a 
    JOIN table_b b 
    ON b.col_name1 = a.col_name1 
WHERE a.candidate_id = 900 
GROUP 
    BY b.candidate_id 
HAVING a.col_name2 = MAX(b.col_name2);