Question

我正在使用此查询来获取total_votes最大的行，但此查询不返回任何行，因此它应返回1行。请帮忙。

SELECT assembly, seat_code, CONCAT(first_name,' ',last_name), total_votes, party_id      
FROM polling JOIN seat USING (seat_id) JOIN candidate USING (candidate_id)
WHERE seat_id=1
HAVING total_votes = MAX(total_votes);

Answer 1

您可以使用MAX聚合并删除HAVING子句。见下文：

SELECT * FROM
(
SELECT 
      assembly, 
      seat_code, 
      CONCAT(first_name,' ',last_name)name, 
      MAX(total_votes)total_votes, 
      party_id      
FROM polling JOIN seat USING (seat_id) JOIN candidate USING (candidate_id)
WHERE seat_id=1
) AS A
HAVING total_votes=(SELECT MAX(total_votes) FROM polling )

Answer 2

  select assembly, seat_code, concat(first_name,' ',last_name), total_votes, party_id     
from (polling join seat using(seat_id) join candidate using(candidate_id))
where seat_id=1 and total_votes=(select max(total_votes) from <table name>);

使用此

mysql查询没有返回任何行

2 个答案: