在mysql中使用group by，导致错误1055

Question

当我尝试使用 mysql 将第一种形式 select 转换为第二种形式时

select id, name ,
(case when years=1992 then cost else 0 end) as year1992,
(case when years=1993 then cost else 0 end) as year1993,
(case when years=1994 then cost else 0 end) as year1994
from pivot 
group by name;

我遇到了一个奇怪的错误

ERROR 1055 (42000): Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'nctest.pivot.id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

这里有什么问题？

------------更新-------------------------

我发现我在使用分组依据时犯了一个错误。

select id, name ,
sum(case when years=1992 then cost else 0 end) as year1992,
sum(case when years=1993 then cost else 0 end) as year1993,
sum(case when years=1994 then cost else 0 end) as year1994
from pivot 
group by id, name;

然后就可以了;;

Answer 1

您正在尝试 SELECT id 列，但您不能，因为它不在 GROUP BY 表达式中。

在mysql中使用group by，导致错误1055

Using group by in mysql, cause error 1055

mysql

pivot

mysql-error-1055