[BUG] 无法存储 Emoji 表情及升级 utf8mb4 时遭遇外键约束错误 (Error 3780)

[Wuxiuga]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

在使用默认数据库 schema 初始化后，尝试向 chat_message 表插入包含 Emoji 表情（如 🔍, ✅）的消息时，报错 Incorrect string value。

Cause: java.sql.SQLException: Incorrect string value: '\xF0\x9F\x94\x8D *...' for column 'content'
...
ERROR 3780 (HY000): Referencing column 'session_id' and referenced column 'id' in foreign key constraint 'chat_message_ibfk_1' are incompatible.

Expected Behavior

验证过的解决方案：修改字符集为utf8mb4，因为有外键约束，修改比较麻烦一些，笔者为mysql8.0版本

-- 1. 临时关闭外键检查，允许结构变更
SET FOREIGN_KEY_CHECKS = 0;

-- 2. 删除子表上的外键约束
ALTER TABLE `chat_message` DROP FOREIGN KEY `chat_message_ibfk_1`;

-- 3. 升级子表 (chat_message) 到 utf8mb4
ALTER TABLE `chat_message` 
CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 4. 升级父表 (chat_session) 到 utf8mb4
ALTER TABLE `chat_session` 
CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 5. 重新创建外键约束
ALTER TABLE `chat_message` 
ADD CONSTRAINT `chat_message_ibfk_1` 
FOREIGN KEY (`session_id`) REFERENCES `chat_session` (`id`) 
ON DELETE CASCADE;

-- 6. 恢复外键检查
SET FOREIGN_KEY_CHECKS = 1;

Steps To Reproduce

No response

Environment

Spring AI Alibaba DataAgent version(s):

Debug logs

No response

Anything else?

No response