Hibernate 4.3.6 QuerySyntaxException:连接所需的路径

Question

我遇到HQL连接查询问题.任何人都可以告诉我,我的下面加入HQL查询有什么问题吗？我使用的是Hibernate 4.3.6,JDK 7和Groovy 2.2

def query = 'select lip.referenceId from Parcel as lip left join TransportFile tf where lip.statusDisplayName != tf.statusDisplayName'
def hqlQuery = session.createQuery(query)
def hqlcount = hqlQuery.list().size

当我运行上面的代码时,我得到以下错误

com.dc.core.common.exception.BaseApplicationException: org.hibernate.hql.internal.ast.QuerySyntaxException: Path expected for join! [select lip.referenceId from com.dc.apps.cp.ebilling.model.impl.Parcel as lip left join TransportFile tf where lip.statusDisplayName != tf.statusDisplayName]

以下是我的包裹实体

package com.dc.apps.cp.ebilling.model.impl
@Entity
@Audited
public class Parcel implements IPersistentEntityInstance {

private static final long                  serialVersionUID = 1L;
private Long                               id;
@AttributeReadPermission(name = "SUBMITTEDFILE.READ")
@AttributeWritePermission(name = "SUBMITTEDFILE.UPDATE")
private File                               submittedFile;
private ParcelType                  type;
private boolean                            isBeingSubmitted;
private TransportFile              transportFile;
}

下面是我的TransportFile实体

package com.dc.apps.cp.legacy.model.impl;
@Entity
@EntityMetadataDefaults(editable = false)
public class TransportFile implements ITransportObject {

private static final long          serialVersionUID = 1L;    
private Long                       id;
private String                     statusDisplayName;    
// [ReferenceID] [varchar](30) NOT NULL
private String                     referenceId;
// [sent] [datetime] NULL,
private Timestamp                  sentDate;
// [received] [datetime] NULL,
private Timestamp                  receivedDate;
// [Status] [varchar](4) NULL,
private String                     statusCode;
private List<TransportLog> TransportLogs;    
private String                     rejectionReason;
}

我在这篇文章中提到了HQL左连接:期望加入的路径,但是我没有看到任何有关我的HQL连接查询的信息.

Answer 1

这个例外"加入的路径"说:

提供从一个实体到另一个实体的路径.连接由映射定义

所以我们需要:

select lip.referenceId 
   from Parcel as lip 
   // instead of this
   // left join TransportFile tf 
   // we need a path from Parcel to TransportFile
   left join lip.transportFile tf 
   where lip.statusDisplayName != tf.statusDisplayName'
   ...

该语句left join TransportFile tf更像是一个SQL ...而不是HQL的情况.

我们的声明必须表达导航:left join lip.transportFile tf- 即加入transportFile与之相关的导航lip.