mysql Like查询使用索引的情况

EXPLAIN SELECT *FROM  `hb_send_list`  WHERE hongbao_id LIKE '%AA1317B32755BDFC1B8036'

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	hb_send_list	ALL	(NULL)	(NULL)	(NULL)	(NULL)	14382	Using where

EXPLAIN SELECT *FROM  `hb_send_list`  WHERE hongbao_id LIKE 'AA1317B32755BDFC1B8036%'

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	hb_send_list	range	hongbao_id	hongbao_id	98	(NULL)	1	Using index condition

EXPLAIN  SELECT *FROM  `hb_send_list`  WHERE hongbao_id LIKE 'A%A1317B32755BDFC1B8036'

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	hb_send_list	range	hongbao_id	hongbao_id	98	(NULL)	995	Using index condition

mysql在使用like查询，%在最前面不会用到索引，中间或最后是会用到索引的，只是越靠前扫描的行数越多