在实行sql server 向 mysql 迁移数据时,报错:
Incorrect string value: '\xF0\x9F\x98\x8A'
原因是mysql 采用的是 utf8 的字符集,而该字符集最多占用三个字节,而一些 表情 需要占用 4个字节,所以需要将 utf8 改成 utf8mb4。
原始配置为:
#mysql 5.5 新增参数 character_set_server=utf8 collation_server=utf8_bin
我将 character_set_server=utf8 改为:character_set_server=utf8mb4,重启mysql 却报错:
发生系统错误 1067 进程意外终止
但是查看错误日志,却没有显示是什么错误信息。有倒腾了一会儿,想到是不是 collation_server 也要修改成 utf8mb4_bin,测试的结果果然如此。
所以要注意在将 MySQL字符集 utf8 改为 utf8mb4 时,一定要注意 collation_server 也要同时修改!
干脆将 default-character-set=utf8mb4 也改成了算了。
最后的字符配置如下:
[mysql] default-character-set=utf8mb4 init_connect='set names utf8mb4' [mysqld] character_set_server=utf8mb4 collation_server=utf8mb4_bin
修改之后,启动成功。

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