如何使用“尺寸"作为 hibernate/jpa 实体中的字段名称? [英] How to use "size" as a field name in a hibernate/jpa entity?

问题描述

我有两个 JPA 实体:VirtualLot 和 VirtualFiles.VirtualFiles 扩展了 VirtualInode.VirtualLot 和 VirtualFiles 之间存在 ManyToMany 关系，描述为 A VirtualLot 可以包含 VirtualFiles" 和 A VirtualFile 可以与多个 VirtualLots"实体定义如下:

I have two JPA entities : VirtualLot and VirtualFiles. VirtualFiles extends VirtualInode. There is a ManyToMany relation between VirtualLot and VirtualFiles described as "A VirtualLot can contain VirtualFiles" and "A VirtualFile can be associated with multiple VirtualLots" The entities are defined as follows :

VirtualFile.java

@Entity
@Table(name = "FIL_FILE")
public class VirtualFile extends VirtualInode {
    //[...]
}

VirtualInode.java

@Entity
@Table(name = "INO_INODE")
@Inheritance(strategy = InheritanceType.JOINED)
public class VirtualInode implements Serializable {
    private Long id; /* The PK */
    private long size = 0L; /* The size */
    // [...]

    /**
     * Default constructor
     */
    public VirtualInode() {
        super();
    }

    /**
     * @return the id
     */
    @Id
    @Column(name = "INO_ID", nullable = false)
    public Long getId() {
        return id;
    }

    /**
     * @return the size
     */
    @Column(name = "INO_SIZE", nullable = false)
    public long getSize() {
        return size;
    }

    //[...]
}

VirtualLot.java

@Entity
@Table(name = "VLT_VIRTUAL_LOT")
public class VirtualLot implements Serializable {
    private Long id; /* The PK */
    private Collection<VirtualFile> files;

    /**
     * Default constructor
     */
    public VirtualLot() {
        super();
    }

    /**
     * @return the id
     */
    @Id
    @Column(name = "VLT_ID", nullable = false)
    public Long getId() {
        return id;
    }


    /**
     * @return the files
     */
    @ManyToMany
    @JoinTable(name = "R001_FIL_VLT", joinColumns = @JoinColumn(name = "VLT_ID", referencedColumnName = "VLT_ID"), inverseJoinColumns = @JoinColumn(name = "INO_ID", referencedColumnName = "INO_ID"))
    public Collection<VirtualFile> getFiles() {
        return files;
    }
    //[...]
}

在这里，我想使用 Spring Data JPA 存储库对给定 VirtualLot 中包含的 VirtualFiles 的大小求和:VirtualLotRepository.查询定义如下:

Here I want to sum the size of the VirtualFiles contained in a given VirtualLot using a Spring Data JPA repository : VirtualLotRepository. The query is defined as follow :

public interface VirtualLotRepository extends JpaRepository<VirtualLot, Long>
{
    @Query("select sum(f.size) from VirtualLot l join l.files f where l.id = ?1")
    long sumFilesSize(long lotId);
}

我的问题是 Hibernate/JPA 混淆了size"关键字，它将它解释为由 hibernate 定义的 SIZE 函数(http://docs.jboss.org/hibernate/orm/4.1/devguide/en-US/html/ch11.html#ql-collection-expressions)

My problem is that Hibernate/JPA messes with the "size" keyword, it interprets it as a SIZE function defined by hibernate (http://docs.jboss.org/hibernate/orm/4.1/devguide/en-US/html/ch11.html#ql-collection-expressions)

结果查询是:

   select
        sum((select
            count(virtualfil2_.VLT_ID) 
        from
            R001_FIL_VLT files1_,
            FIL_FILE virtualfil2_ 
        inner join
            INO_INODE virtualfil2_1_ 
                on virtualfil2_.INO_ID=virtualfil2_1_.INO_ID 
        where
            virtuallot0_.VLT_ID=files1_.VLT_ID 
            and files1_.INO_ID=virtualfil2_.INO_ID)) as col_0_0_ 
    from
        VLT_VIRTUAL_LOT virtuallot0_ 
    inner join
        R001_FIL_VLT files1_ 
            on virtuallot0_.VLT_ID=files1_.VLT_ID 
    inner join
        FIL_FILE virtualfil2_ 
            on files1_.INO_ID=virtualfil2_.INO_ID 
    inner join
        INO_INODE virtualfil2_1_ 
            on virtualfil2_.INO_ID=virtualfil2_1_.INO_ID 
    where
        virtuallot0_.VLT_ID=?

这(显然)不起作用.我希望它是这样的:

which (obviously) doesn't work. I want it to be this :

   select
        sum(virtualfil2_1_.INO_SIZE)
    from
        VLT_VIRTUAL_LOT virtuallot0_ 
    inner join
        R001_FIL_VLT files1_ 
            on virtuallot0_.VLT_ID=files1_.VLT_ID 
    inner join
        FIL_FILE virtualfil2_ 
            on files1_.INO_ID=virtualfil2_.INO_ID 
    inner join
        INO_INODE virtualfil2_1_ 
            on virtualfil2_.INO_ID=virtualfil2_1_.INO_ID 
    where
        virtuallot0_.VLT_ID=?

哪个适用于我的 SQL 暂存器(带有正确的?"值).

Which works in my SQL scratchpad (with a proper '?' value).

是否可以告诉 Hibernate/JPA size 是我的 VirtualInode/VirtualFile 实体的 size 属性而不是 SIZE 函数?

我已经尝试过双引号转义，但不起作用.我使用的是 Oracle10g 方言.

I have already tried double-quotes escaping and that doesn't work. I use an Oracle10g dialect.

如果我将重复的属性 fsize 添加到我的 VirtualInode 实体并在我的请求中使用它，它可以工作，但这不是我正在寻找的解决方案.

EDIT : If I add a duplicate property fsize to my VirtualInode entity and use it in my request, it works, but that not the solution I'm looking for.

VirtualInode.java

@Column(name = "INO_SIZE", nullable = false, updatable = false, insertable = false)
public long getFsize() {
    return getSize();
}

public void setFsize(final long size) {
    setSize(size);
}

VirtualLotRepository.java

@Query("select sum(f.fsize) from VirtualLot l join l.files f where l.id = ?1")
long sumFilesSize(long lotId);

推荐答案

size 是保留关键字，类似于 Java 中的 default 或 for.因此，要么在 perhabs nodeSize 中更改变量的名称，要么使用带有 name 属性的 @Column(name = "nodeSize") 注释给一个基本列一个特殊的名字.

size is a reserved keyword like default or for in Java. Therefore either change your name for your variable in perhabs nodeSize or use the @Column(name = "nodeSize") Annotation with the name attribute to give a basic column a special name.

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