show innodb status的Record lock, heap no 2 PHYSICAL RECORD: n_fields 3的困惑？

delete from t_lock_1 where a=10
2018-05-24T09:31:53.082148Z 26 [Note] InnoDB: * (1) WAITING FOR THIS LOCK TO BE GRANTED:

RECORD LOCKS space id 209 page no 3 n bits 72 index PRIMARY of table test.t_lock_1 trx id 17766 lock_mode X locks rec but not gap waiting
Record lock, heap no 2 PHYSICAL RECORD: n_fields 3; compact format; info bits 32
0: len 4; hex 8000000a; asc ;;
1: len 6; hex 000000004565; asc Ee;;
2: len 7; hex 4f000001df0871; asc O q;;

mysql初学者，
上面是我人为的模拟死锁后，show innodb status的部分输出；
下面是 t_lock_1的表定义，

1 row in set (0.00 sec)

mysql> show create table t_lock_1\G;
1. row **

   Table: t_lock_1

Create Table: CREATE TABLE t_lock_1 (
a int(11) NOT NULL,
PRIMARY KEY (a)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

疑问是下面的部分：
Record lock, heap no 2 PHYSICAL RECORD: n_fields 3; compact format; info bits 32
0: len 4; hex 8000000a; asc ;;
1: len 6; hex 000000004565; asc Ee;;
2: len 7; hex 4f000001df0871; asc O q;;
疑问一：
n_fields 3 ，表示的是包括3个字段，（这个理解应该没错吧）
我的t_lock_1就一个字段，那下面的怎么出现3列？
疑问2：
hex 8000000a ，有啥方法转出十进制的数？