如何用嵌入式id编写JPQL SELECT？ [英] How to write JPQL SELECT with embedded id?

问题描述

我正在使用Toplink essentials（JPA）+ GlassFish v3 + NetBean 6.9

I'm using Toplink essentials (JPA) + GlassFish v3 + NetBean 6.9

我有一个包含复合主键的表：

I have one table with composite primary key:

table (machine)
----------------
|PK machineId  |
|PK workId     |
|              |
|______________|

我为实体本身创建了2个实体类，第二个是PK类。

I created 2 entity classes one for entity itself and second is PK class.

public class Machine {
   @EmbeddedId
   protected MachinePK machinePK;

   //getter setters of fields..
}

public class MachinePK {
    @Column(name = "machineId")
    private String machineId;

    @Column(name = "workId")
    private String workId;

}

现在.. 如何编写SELECT子句JPQL with WHERE ???

此失败。

SELECT m FROM Machine m WHERE m.machineId = 10

http://www.mail-archive.com/[e-mail]/msg03073。 html

根据网页，添加val？不，它也失败了。

According to the web page, add "val"? No it fails too.

   SELECT m FROM Machine m WHERE m.machineId.val = 10

在这两种情况下，错误都是：

In both case, the error is:

    Exception Description: Error compiling the query 
[SELECT m FROM Machine m WHERE m.machineId.val = 10], 
line 1, column 30: unknown state or association field 
[MachineId] of class [entity.Machine].

推荐答案

SELECT m FROM Machine m WHERE m.machinePK.machineId = 10

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