当我在另一个查询中嵌套一个查询时，出现错误 "SQL error 1241 operand should contain 5 column(s)"

Question

SELECT *
FROM AUTHOR
WHERE FLOOR(DATEDIFF(bDate,CURDATE())/365.25*-1) > 30 AND
    (SELECT a.*
    FROM AUTHOR a 
    WHERE (SELECT count(paperId) from AUTHOR_PAPER ap where ap.authorId = a.aEmail)) > 3

这两个查询都是独立工作的，我只想找出两个 where 子句

表格

author
(aEmail*
,fName
,lName
,bDate
,city
)

reviewer
(rEmail*
,phoneNumber
,lName
,fName
,city
)

paper
(paperId*
,title
,abstract
,submissionDate
)

author_paper
(authorId*
,paperId*
,isContact
)

paper_review
(paperId*
,reviewerId*
,score 
,reviewSubmissionDate
,reviewInvitationDate
)

* = (component of) PRIMARY KEY

我得到的错误是：17:05:14 SELECT * FROM AUTHOR WHERE FLOOR(DATEDIFF(bDate,CURDATE())/365.25-1) > 30 AND (SELECT a. FROM AUTHOR a WHERE (SELECT count(*) from AUTHOR_PAPER ap where ap.authorId = aEmail)) > 3 LIMIT 0, 1000 错误代码： 1241. 操作数应包含 5 列 0.000 秒

aEmail = authorId

Answer 1

您似乎需要 30 岁以上且发表了 3 篇以上论文的作者。如果是这样，我会推荐：

select *
from author a
where 
    bdate <= current_date - interval 31 year
    and (select count(*) from author_paper ap where ap.authorid = a.email) > 3

当我在另一个查询中嵌套一个查询时，出现错误 "SQL error 1241 operand should contain 5 column(s)"

When I nest a query within another query I am getting the error "SQL error 1241 operand should contain 5 column(s)"

mysql

subquery

where-clause