Error querying database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'ie_llyh.u.ChkPlanID'; this is incompatible with sql_mode=only_full_group_by

Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'ie_llyh.u.ChkPlanID'; this is incompatible with sql_mode=only_full_group_by

1 Reason:

Use group_concat in SQL to combine, if you are other group by reason, please find other solutions

Online explanation:

After mysql5.7.5, the default opened online, so some SQL could not be executed normally, in fact, it is caused by our SQL irregular, because some of the data returned is uncertain, so this will appear mistake.

2 solution

method one

Code modified SQL

Rewriting involving the SQL section of Group_Concat

example

Table Class Class Table

• Field CID class ID

ClassUser class student correspondence table

• Field ID primary key
• Field CID class ID
• Field UID Student ID

Table UserInfo student information table

• Field UID Student ID
• Field Name Student Name

Original code

 select a.cid
        GROUP_CONCAT(c.name SEPARATOR ',') as allName
             from class a
        LEFT JOIN classUser b ON a.cid = b.cid
        LEFT JOIN UserInfo c ON c.uid = b.uid
        WHERE 1=1 

After modification

   select   a.cid
        b.name as allName
        from class a
         LEFT JOIN (
			select  GROUP_CONCAT(b.name SEPARATOR ',') as name , a.cid  from classUser  a 
            left join UserInfo b on a.uid = b.uid
			group by a.cid 
        )b on a.cid = b.cid
        where 1=1

Method 2 (online method is not verified)

Close ONLY_FULL_GROUP_BY, I am Linux environment, I just talk about Linux solution:

Log in into MySQL

Linux login: mysql -u username -p, then enter the password, enter SQL: show variables like '% SQL_MODE';

Edit my.cnf file

File address is usually: /etc/my.cnf/eetc/mysql/my.cnf
Find the position of SQL-mode, remove online, then restart mysql
There is no SQL-MODE in my.cnf, you need to join:

sql-mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION 

Restart the mysql service after successful

Service MySQL Restart, after restart, log in to Mysql, enter SQL: show variables like '% SQL_MODE'; if there is no online, it is already successful.