我使用 Spring Boot 2 和 thymeleaf 来显示现有 Oracle 12 数据库中的数据。
工作流实体是我想显示的主要实体之一:
@Entity
@Immutable
@Table(name = "V_AV_WFPROC", schema="avuser")
public class Workflow {
@Id
@Column(name = "proc_id")
private Long id;
private String name;
@Column(name = "proc_ref")
private String procRef;
private String description;
@OneToOne(mappedBy = "workflow")
private WorkflowCategory workflowCategory;
public Long getId() {
return id;
}
public String getName() {
return name;
}
public String getProcRef() {
return procRef;
}
public String getDescription() {
return description;
}
public WorkflowCategory getWorkflowCategory() {
return workflowCategory;
}
}
workflowCategory 保存有关工作流程的一些信息，例如工作流程的类型:
@Entity
@Immutable
@Table(name = "V_AV_WFPROC_CATEGORIES", schema = "avuser")
public class WorkflowCategory {
@Id
@Column(name = "cat_id")
private Long id;
private String name;
@OneToOne
@JoinColumn(name="proc_id", referencedColumnName = "proc_id")
private Workflow workflow;
public Long getId() {
return id;
}
public String getName() {
return name;
}
public Workflow getWorkflow() {
return workflow;
}
我有一个工作流类别的自定义查询，因为只有一些信息对我来说很重要。我需要解码类别名称，因为我无权访问存储信息的表。
@Repository
public interface WorkflowCategoryRepository extends CrudRepository<WorkflowCategory, String>{
@Query(value = "SELECT PROC_ID || CAT_ID AS CAT_ID, PROC_ID, DECODE(CAT_ID, 4, 'Request Workflow', 5, 'Approval Workflow', 6, 'Escalation Workflow', 7, 'Fulfillment Workflow', 51, 'Custom Tasks Workflow', '?') AS NAME FROM WorkflowCategory WHERE CAT_ID IN (4, 5, 6, 7, 51)",
nativeQuery = true)
public Iterable<WorkflowCategory> findAll();
}
如果我尝试访问数据，我会收到以下错误消息。
More than one row with the given identifier was found: 41, for class: de.elementity.runbook.workflow.WorkflowCategory
该表包含每个工作流程的更多信息，但只有查询中的信息对我来说很重要。如何指定 @OneToOne 映射的查询？
我还尝试使用 @ManyToMany 映射，但收到以下错误消息:
2020-02-10 14:48:14.057 DEBUG 35572 --- [nio-8080-exec-1] org.hibernate.SQL : select wfcats0_.workflows_proc_id as workflows_proc_id2_12_0_, wfcats0_.wfCats_cat_id as wfCats_cat_id1_12_0_, wfcat1_.cat_id as cat_id1_11_1_, wfcat1_.name as name2_11_1_ from V_AV_WFPROC_CATEGORIES_V_AV_WFPROC wfcats0_ inner join avuser.V_AV_WFPROC_CATEGORIES wfcat1_ on wfcats0_.wfCats_cat_id=wfcat1_.cat_id where wfcats0_.workflows_proc_id=?
2020-02-10 14:48:14.221 WARN 35572 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 972, SQLState: 42000
2020-02-10 14:48:14.221 ERROR 35572 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper : ORA-00972: idnetifier too long
2020-02-10 14:48:14.229 ERROR 35572 --- [nio-8080-exec-1] org.thymeleaf.TemplateEngine : [THYMELEAF][http-nio-8080-exec-1] Exception processing template "workflows": An error happened during template parsing (template: "class path resource [templates/workflows.html]")
org.thymeleaf.exceptions.TemplateInputException: An error happened during template parsing (template: "class path resource [templates/workflows.html]")
当我从查询中删除 DECODE 部分时，也会发生这种情况。
最佳答案
您可以尝试在 @OneToOne 注释上使用以下属性吗？
cascade = CascadeType.ALL and orphanRemoval = true
关于java - 使用 OneToOne 映射的 Spring Boot 2 自定义查询，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/60166533/