无法调出mysql数据表

mysql -u username -p -h hostname -P port

mysql -u root -p -h localhost -P 3306

SHOW GRANTS FOR 'username'@'hostname';

SHOW GRANTS FOR 'root'@'localhost';

GRANT SELECT, INSERT, UPDATE, DELETE ON database_name.table_name TO 'username'@'hostname';

GRANT SELECT, INSERT, UPDATE, DELETE ON mydb.mytable TO 'root'@'localhost';

SELECT * FROM database_name.table_name;

SELECT * FROM mydb.mytable;

SHOW TABLES LIKE 'table_name';

SHOW TABLES LIKE 'mytable';

CREATE TABLE table_name (
    column1 datatype,
    column2 datatype,
    ...
);

CREATE TABLE mytable (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(255),
    age INT
);