【问题标题】:OneToMany relationship not working一对多关系不起作用
【发布时间】:2016-09-07 00:09:08
【问题描述】:

我想使用 kundera 作为框架并使用 cassandra 作为我的数据库,在我的传感器类与碎片类之间创建关系:

我想做的是:每个传感器都关联到很多部分:

传感器 1____0 * 个

但在进行此配置后(如下),我得到了两个没有任何关系的单独表:

 idsensor | date  | event_time               | pressure | temperature
----------+-------+--------------------------+----------+-------------
        1 | 33544 | 1970-01-01 00:00:00+0000 |       10 |          10

(1 rows)
cqlsh:sensor> select * from pieces;

 idpiece | date | depth | event_time | height | idsensor | sensorkey | width
---------+------+-------+------------+--------+----------+-----------+-------
       1 | null |    12 |       null |     11 |     null |      null |    10

关键类:

@Embeddable
public class SensorKey
{
    @Column 
    private String idsensor;           
    @Column 
    private long date;           
    @Column(name = "event_time")
    private long eventTime;

传感器类

   public class SensorEntitie implements Serializable {
    @EmbeddedId
    private SensorKey sensorkey;
    @Column
    private float temperature;
    @Column
    private float pressure;
    @OneToMany(cascade = { CascadeType.ALL }, fetch = FetchType.EAGER)
    @JoinColumns({
        @JoinColumn(name = "idsensor", referencedColumnName = "idsensor"),
        @JoinColumn(name = "date", referencedColumnName = "date",
            insertable = false, updatable = false),
        @JoinColumn(name = "event_time", referencedColumnName = "event_time",
            insertable = false, updatable = false)
})
    private Set<PieceEntitie> pieces;

件类:

public class PieceEntitie implements Serializable{


    @Id
    private String idpiece;
    @Column
    private double width;
    @Column
    private double height;
    @Column
    private double depth;

教程如下; https://github.com/impetus-opensource/Kundera/wiki/Polyglot-Persistence

我怎样才能建立这种关系?

【问题讨论】:

  • 这个问题解决了吗?
  • 不,我没有找到任何解决方案

标签: java hibernate cassandra one-to-many kundera


【解决方案1】:

使用 Cassandra 3 后问题解决

因为在我使用 cassandra 2.1 之前

【讨论】:

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