My query is not using indexes. It is a simple query. Can someone explain why that's the case?
The query:
select TIME_FORMAT(start_time,'%H:%i') start_time,
TIME_FORMAT(end_time,'%H:%i') end_time,
rule_id, day_of_week, long_message,
short_message, rotation_weight, mode
from timed_delivery_messages order by rule_id asc;
Explain Plan:
+----+-------------+-------------------------+-------+---------------+---------+---------+------+------+-------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------------------------+-------+---------------+---------+---------+------+------+-------+
| 1 | SIMPLE | timed_delivery_messages | index | NULL | PRIMARY | 4 | NULL | 22 | |
+----+-------------+-------------------------+-------+---------------+---------+---------+------+------+-------+
1 row in set (0.00 sec)
Table:
mysql> show create table timed_delivery_messages\G
*************************** 1. row ***************************
Table: timed_delivery_messages
Create Table: CREATE TABLE `timed_delivery_messages` (
`row_create` datetime DEFAULT NULL,
`row_mod` datetime DEFAULT NULL,
`rule_id` int(11) NOT NULL,
`start_time` time DEFAULT NULL,
`end_time` time DEFAULT NULL,
`day_of_week` varchar(7) DEFAULT NULL,
`rotation_weight` varchar(50) DEFAULT NULL,
`mode` varchar(10) DEFAULT 'active',
`long_message` varchar(256) DEFAULT NULL,
`short_message` varchar(256) DEFAULT NULL,
PRIMARY KEY (`rule_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)
