我使用以下注释配置了ManyToMany关系:
@ManyToMany
@JoinTable(name="back_date_entry_project",
joinColumns={@JoinColumn(name="back_date_entry_id")},
inverseJoinColumns={@JoinColumn(name="project_id", columnDefinition="INT(10) UNSIGNED")},
foreignKey=@ForeignKey(name="fk_back_date_entry_project_back_date_entry_back_date_entry_id"),
inverseForeignKey=@ForeignKey(name="fk_back_date_entry_project_project_project_id"),
uniqueConstraints=@UniqueConstraint(columnNames={"back_date_entry_id","project_id"})
)
private Set<Project> projects;
此配置在创建连接表时添加键:
KEY `fk_back_date_entry_project_project_project_id` (`project_id`),
Join Table创建如下::
mysql> show create table back_date_entry_project ;
+-------------------------+------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+-------------------------+------------------------------------------------------------------------------------------------------------------------------------------------+
| back_date_entry_project | CREATE TABLE `back_date_entry_project` (
`back_date_entry_id` int(10) unsigned NOT NULL,
`project_id` int(10) unsigned NOT NULL,
PRIMARY KEY (`back_date_entry_id`,`project_id`),
KEY `fk_back_date_entry_project_project_project_id` (`project_id`),
CONSTRAINT `fk_back_date_entry_project_back_date_entry_back_date_entry_id` FOREIGN KEY (`back_date_entry_id`) REFERENCES `back_date_entry` (`back_date_entry_id`),
CONSTRAINT `fk_back_date_entry_project_project_project_id` FOREIGN KEY (`project_id`) REFERENCES `project` (`project_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+-------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
如果我使用select查询,请将结果显示为::
mysql> select * from back_date_entry_project ;
+--------------------+------------+
| back_date_entry_id | project_id |
+--------------------+------------+
| 1 | 65 |
| 3 | 65 |
| 2 | 85 |
| 2 | 95 |
| 1 | 99 |
+--------------------+------------+
5 rows in set (0.00 sec)
此结果按project_id排序?
如何在sql控制台中使用back_date_entry_id
对其进行排序?
答案 0 :(得分:1)
If you don't specify order by you can't be sure about order.
编辑:
@ManyToMany
@JoinTable(name="back_date_entry_project",
joinColumns={@JoinColumn(name="back_date_entry_id")},
inverseJoinColumns={@JoinColumn(name="project_id", columnDefinition="INT(10) UNSIGNED")},
foreignKey=@ForeignKey(name="fk_back_date_entry_project_back_date_entry_back_date_entry_id"),
inverseForeignKey=@ForeignKey(name="fk_back_date_entry_project_project_project_id"),
uniqueConstraints=@UniqueConstraint(columnNames={"back_date_entry_id","project_id"})
)
@OrderBy(value="nameOfTheProjectColumn asc/desc")
@OrderColumn(name="back_date_entry_id")
private Set<Project> projects;
@OrderBy将适用于项目属性。
您可以尝试使用@OrderColumn(名称=&#34; back_date_entry_id&#34;)