mysql 读取乱码

-- 查看当前数据库字符集
SHOW VARIABLES LIKE 'character_set_database';

-- 修改数据库字符集
ALTER DATABASE your_database_name CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 修改表字符集
ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 修改字段字符集
ALTER TABLE your_table_name MODIFY your_column_name VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 查看当前数据库排序规则
SHOW VARIABLES LIKE 'collation_database';

-- 修改数据库排序规则
ALTER DATABASE your_database_name CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 修改表排序规则
ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

jdbc:mysql://localhost:3306/your_database_name?useUnicode=true&characterEncoding=utf8mb4

[mysqld]
character-set-server=utf8mb4
collation-server=utf8mb4_unicode_ci