mysql报错In aggregated query without GROUP BY

执行语句：
select de.dept_no, count(s.salary) from salaries s left join dept_emp de on s.emp_no = de.emp_no;

完整报错信息：
In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'demos.de.dept_no'; this is incompatible with sql_mode=only_full_group_by

经过查找资料，问题是Mysql版本5.7以上会有这个错，更改sql_mode即可。

# 查看sql_mode
select version(), @@sql_mode;

# 更改sql_mode
SET sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));

更改设置之后，问题解决。

参考博客：
https://cloud.tencent.com/developer/article/1404739