Mysql问题解决: ERROR 1055 (42000)

错误代码：

ERROR 1055 (42000) at line 4: Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated column this is incompatible with sql_mode=only_full_group_by

解决方法1：

将未进行分组统计的其他列全部加入到group by后面

select 
Company.company_code, 
Company.founder,
count(distinct Lead_Manager.lead_manager_code), 
count(distinct Senior_Manager.senior_manager_code),
count(distinct Manager.manager_code),
count(distinct Employee.employee_code)
from Company
    left join Lead_Manager on Company.company_code = Lead_Manager.company_code
    left join Senior_Manager on Lead_Manager.lead_manager_code = Senior_Manager.lead_manager_code
    left join Manager on Senior_Manager.senior_manager_code = Manager.senior_manager_code
    left join Employee on Manager.manager_code = Employee.manager_code
group by Company.company_code,Company.founder
order by Company.company_code;

上面sql的问题链接： New Companies | HackerRank

解决方法2：

​​​​​​MySQL问题：ERROR 1055 (42000): Expression #2 of SELECT list is not in GROUP BY_微步_ym的博客-CSDN博客