如何确定SQL语句是否会运行？

Question

告诉我查询是否正确，或包含任何错误：

select cname from company where id IN (
    select company_id,count(*) from medication 
    group by(company_id) having count(*)>1 
) 
order by cname; 

Answer 1

供您参考。您可以随时在MySQl/PHPMyadmin上运行您的查询，以便显示您的错误。

另外，您可以使用以下工具

https://www.piliapp.com/mysql-syntax-check/

http://sqlfiddle.com/

我希望它能帮助

Answer 2

包含你不能在（选择COMPANY_ID，计数（） 错误删除计数（）可能适合您，请检查以下

个

/* 
create table company(id int,cname varchar(10)); 
insert into company values 
(1,'abc'),(2,'def'),(3,'ghi'); 

create table medication(id int,company_id int); 
truncate table medication; 
insert into medication values 
(1,1), 
(2,1), 
(3,1), 
(4,2), 
(5,2), 
(6,2), 
(7,3), 
(8,2); 
*/ 

这个代码

select cname from company 
where id IN (select company_id from medication group by(company_id) having count(*) > 1) 
order by cname; 

结果

+-------+ 
| cname | 
+-------+ 
| abc | 
| def | 
+-------+