修改MySQL数据库编码

ALTER DATABASE 数据库名称  CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

SELECT CONCAT('ALTER TABLE ', table_name, ' CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;') AS alter_sql
FROM information_schema.tables
WHERE table_schema = '数据库名称 ';