1267-Illegal mix of collations (

今天LEFT JOIN 表，报如下错误：
1267-Illegal mix of collations (utf8mb4_general_ci,IMPLICIT) and (utf8mb4_0900_ai_ci,IMPLIC for operation '=')

出现这种问题就是关联表的字符集不匹配

1.查看数据库的字符集

show variables where Variable_name like 'collation%';

结果：

image

2.查看关联表字符集

 show create table table_name;

3.给关联表设置字符编码

alter table table_name default character set utf8mb4 collate=utf8mb4_general_ci;

4.给关联表字段设置字符编码

 ALTER TABLE table_name convert to CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;