1

您好有以下实体；

@Entity
public class FilesInfo {
    @Id
    @GeneratedValue
    private Integer id;
    private String name;
    private String url;

    @OneToMany(cascade= CascadeType.ALL)
    @JoinColumn(name="fileId")
    private Collection<FilesShare> filesShared = new ArrayList<FilesShare>();

    public Collection<FilesShare> getFilesShared() {
        return filesShared;
    }

    public void setFilesShared(Collection<FilesShare> filesShared) {
        this.filesShared = filesShared;
    }
 //getters & setters   
}

另一个

@Entity
public class FilesShare {
    private Integer id;
    private int userId;
    private int owner;
}

结果和表格是：

mysql> desc filesshare;
+--------+---------+------+-----+---------+----------------+
| Field  | Type    | Null | Key | Default | Extra          |
+--------+---------+------+-----+---------+----------------+
| id     | int(11) | NO   | PRI | NULL    | auto_increment |
| userId | int(11) | NO   |     | NULL    |                |
| owner  | int(11) | NO   |     | NULL    |                |
| fileId | int(11) | YES  | MUL | NULL    |                |
+--------+---------+------+-----+---------+----------------+
4 rows in set (0.01 sec)

mysql> desc filesinfo;
+-------+--------------+------+-----+---------+----------------+
| Field | Type         | Null | Key | Default | Extra          |
+-------+--------------+------+-----+---------+----------------+
| id    | int(11)      | NO   | PRI | NULL    | auto_increment |
| name  | varchar(255) | YES  |     | NULL    |                |
| url   | varchar(255) | YES  |     | NULL    |                |
+-------+--------------+------+-----+---------+----------------+
3 rows in set (0.00 sec)

我想制作 hql，因为我制作了下面的 sql：

    select a.id, a.name, a.url from FilesInfo a inner join FilesShare b 
on a.id=b.fileid where b.userid=5 and b.owner=1;

给出以下输出：

mysql> select a.id, a.name, a.url from FilesInfo a inner join FilesShare b on a.
id=b.fileid where b.userid=5 and b.owner=1;
+----+-------------------+-------------------------------------+
| id | name              | url                                 |
+----+-------------------+-------------------------------------+
|  1 | dwnld_btn_1.png   | C:\shareapp\admin\dwnld_btn_1.png   |
|  2 | dwnld_btn_1.png   | C:\shareapp\admin\dwnld_btn_1.png   |
|  3 | dwnld_btn_1.png   | C:\shareapp\admin\dwnld_btn_1.png   |
|  4 | dwnld_btn_1_1.png | C:\shareapp\admin\dwnld_btn_1_1.png |
+----+-------------------+-------------------------------------+

我尝试了以下 hql：

select a.id, a.name, a.url from FilesInfo a inner join FilesShare b 
where a.id=b.fileid and b.userid=5 and b.owner=1

但我收到了这个错误

预计加入的路径！[select a.id, a.name, a.url from app.domain.FilesInfo a 内部加入 FilesShare b where a.id=b.fileid and b.userid=5 and b.owner=1]

现在怎么做inner join，是个问题

谢谢你

4

2 回答 2

3

您的查询需要路径，详情可以参考这个问题：HQL ERROR: Path expected for join。

所以，这样的事情应该解决它：

select a.id, a.name, a.url from FilesInfo a inner join a.filesShared b where b.userid=5 and b.owner=1;

但我只会在您的 FilesShare 中有一个 ManyToOne 映射：

private FilesInfo filesInfo;

@ManyToOne
@JoinColumn(name = "id")
public FilesInfo getFilesInfo() {
    return filesInfo;
}

public void setFilesInfo(FilesInfo filesInfo) {
    this.filesInfo = filesInfo;
}

并做这个查询

from FilesShare where userId = 5 and owner = 1

它看起来更好，并返回文件共享列表，每个文件共享都filesInfo填充了 parent ( ) 字段。

于 2013-04-27T08:13:18.647 回答
0

将 spring 数据版本更新为 1.10.4.RELEASE，这解决了问题。

于 2017-11-30T20:53:29.827 回答