为什么这个MySql查询（在分区表上）总是命中第一个分区？

我正在使用分区创建一个表，如下所示：

CREATE TABLE `alert` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `eventId` int(10) unsigned NOT NULL,
  `occurred` datetime NOT NULL,
  KEY `id` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin
/*!50100 PARTITION BY RANGE (TO_DAYS(occurred))
(PARTITION 28_06 VALUES LESS THAN (735413) ENGINE = InnoDB,
 PARTITION 29_06 VALUES LESS THAN (735414) ENGINE = InnoDB,
 PARTITION 30_06 VALUES LESS THAN (735415) ENGINE = InnoDB,
 PARTITION 01_07 VALUES LESS THAN (735416) ENGINE = InnoDB,
 PARTITION 02_07 VALUES LESS THAN (735417) ENGINE = InnoDB,
 PARTITION 03_07 VALUES LESS THAN (735418) ENGINE = InnoDB,
 PARTITION 04_07 VALUES LESS THAN (735419) ENGINE = InnoDB,
 PARTITION 05_07 VALUES LESS THAN (735420) ENGINE = InnoDB,
 PARTITION 06_07 VALUES LESS THAN (735421) ENGINE = InnoDB,
 PARTITION 07_07 VALUES LESS THAN (735422) ENGINE = InnoDB) */

一切似乎都正常工作，但当我执行以下查询时：

EXPLAIN PARTITIONS SELECT * FROM alert WHERE occurred >= '2013-06-30' AND occurred <= '2013-07-01';

为什么分区

28_06

出现在这些结果中？当我非常清楚地选择开始时

2013-06-30

有什么想法吗

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奇怪的是，以下查询似乎很好：

EXPLAIN PARTITIONS SELECT * FROM alert WHERE occurred >= '2013-07-02' AND occurred <= '2013-07-04';

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看起来这是一个回归错误。我在Mac OS X 10.8上使用的是5.6.11版

解决方案是在开始时创建一个从未使用过的分区。i、 e:

PARTITION unused VALUES LESS THAN (0)

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看起来这是一个回归错误。我在Mac OS X 10.8上使用的是5.6.11版

解决方案是在开始时创建一个从未使用过的分区。i、 e:

PARTITION unused VALUES LESS THAN (0)

PARTITION unused VALUES LESS THAN (0)