rust使用mysql插入数据

Rust使用mysql库的时候，插入数据报错

问题相关代码

    //连接数据库    let url = "mysql://root:[email protected]/Contract";    let pool = Pool::new(url).unwrap();    let mut conn = pool.get_conn().unwrap();    //插入数据    conn.exec_drop(    "INSERT INTO Contract_info (name, totalSupply) VALUES (:name, :totalSupply)",        params! {            "name"=>"name",             "totalSupply"=>"totalSupply",         },    ).unwrap();

运行结果及报错内容

thread 'main' panicked at 'called Result::unwrap() on an Err value: MySqlError { ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '?Supply, ?, ?, ?)' at line 1 }',