CREATE TABLE t1 (Id INT, AtTime DATETIME, KEY AtTime (AtTime));
SET NAMES CP850;
INSERT INTO t1 VALUES (1,'2010-04-12 22:30:12'), (2,'2010-04-12 22:30:12'), (3,'2010-04-12 22:30:12');
EXPLAIN EXTENDED SELECT * FROM t1 FORCE INDEX(attime) WHERE AtTime = '2010-02-22 18:40:07';
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ref AtTime AtTime 9 const 1 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`Id` AS `Id`,`test`.`t1`.`AtTime` AS `AtTime` from `test`.`t1` FORCE INDEX (`attime`) where (`test`.`t1`.`AtTime` = '2010-02-22 18:40:07')