Question

我在两个表之间有OneToMany / ManyToOne的关系。表Partition中的外键引用id Event。当我致电event.getPartitions()时，应该在一个Partitions中返回包含所有Event的列表，我会遇到以下例外情况：

Caused by: org.hibernate.exception.SQLGrammarException: could not extract ResultSet.
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax.

dialect设为org.hibernate.dialect.MySQL5Dialect，driver class为com.mysql.jdbc.Driver。

getPartitions：

@XmlTransient
@OneToMany(mappedBy = "event")
public Collection<Partition> getPartitions()
{
    return partitions;
}

getEvent：

@XmlTransient
@ManyToOne
@JoinColumn(name = "event_id", referencedColumnName = "id", nullable = false)
public Event getEvent()
{
    return event;
}

事件：

DROP TABLE IF EXISTS `event`;
CREATE TABLE `event` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` varchar(1024) NOT NULL,
  `description` varchar(1024) DEFAULT NULL,
  `img` varchar(1024) DEFAULT NULL,
  `date` date DEFAULT NULL,
  `location` varchar(1024) DEFAULT NULL,
  `information` varchar(1024) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

分区：

DROP TABLE IF EXISTS `partition`;
CREATE TABLE `partition` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `event_id` int(11) NOT NULL,
  `title` varchar(1024) DEFAULT NULL,
  `description` varchar(1024) DEFAULT NULL,
  `active_timestamp` datetime DEFAULT NULL,
  `position` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `event_id` (`event_id`),
  CONSTRAINT `event_partition` FOREIGN KEY (`event_id`) REFERENCES `event` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=utf8;

以下查询得到了解释，对我来说也很合适：

10:44:04,708 INFO  [stdout] (default task-4) Hibernate: select event0_.id as id1_1_0_, event0_.date as date2_1_0_, event0_.description as descript3_1_0_, event0_.img as img4_1_0_, event0_.information as informat5_1_0_, event0_.location as location6_1_0_, event0_.title as title7_1_0_ from Event event0_ where event0_.id=?
10:44:04,818 INFO  [stdout] (default task-4) Hibernate: select partitions0_.event_id as event_id6_1_0_, partitions0_.id as id1_2_0_, partitions0_.id as id1_2_1_, partitions0_.active_timestamp as active_t2_2_1_, partitions0_.description as descript3_2_1_, partitions0_.event_id as event_id6_2_1_, partitions0_.position as position4_2_1_, partitions0_.title as title5_2_1_ from Partition partitions0_ where partitions0_.event_id=?

Answer 1

在MySQL中，

Partition为reserved word，将表名更改为其他名称（实体名称可以保持不变，只需使用@Table注释来配置新表名。）

Hibernate OneToMany / ManyToOne导致SQLGrammarException

1 个答案: