使用 Criteria API 和 Annotation 在 Hibernate 中连接两个表 [英] Join two tables in Hibernate with Criteria API and Annotation

问题描述

我想用 Hibernate Annotations 和 Criteria 在 MySQL 中加入 2 个表例如:

I want to join 2 tables in MySQL with Hibernate Annotations and Criteria Like for example:

我有 2 个表，候选人和工作，每个表有 2 列:

I have 2 tables, candidates and jobs, having 2 columns each:

• 候选人:candID &名字

• 工作:jobID &工作名称

• candidates: candID & candName

• jobs: jobID & jobName

                        candidates                     jobs       
              candID    candName          jobID          jobName
                  1          abc                       1               job1
                  2          xyz                       2               job2

我需要在 Hibernate 的 Criteria 中创建一个查询:

i need to create a query in Criteria in hibernate as:

 select candName  ,jobName    from candidates as c ,jobs as j  
 where c.candID = j.jobID where candName = abc and jobName=job1

对此的标准查询是什么，最重要的是我将在我的注释类中写什么(因为我使用的是 spring 注释)，我是否需要在我的申请者上下文.xml 中写任何东西...

what will be the criteria query for that and most importantly what will i write in my annotation class ( as i am using spring annotations) and do i need to write anything in my applicantioncontext.xml...

谢谢

如果您能帮助我，我将非常感激，因为我在过去 3 天里一直在为它而苦苦挣扎，但没有成功

I will be really greatful if you can help me with that as i am struggling for last 3 days for it with no success

谢谢

推荐答案

假设每个类的层次结构表，其中 Candidates 和 Jobs 对应于他们的数据库实体

Assuming table per class Hierarchy, where Candidates and Jobs correspond to their database entities

public class Candidates{
//define Generative stretegy if this is primary key, and other JPA annotations, with cascade
  private Long CandId;
//getters and setters
//define other properties here

}
/*Like wise for Jobs class */

我不检查 IDE/编译器内部，但它应该类似于下面

I donot check inside an IDE/Compiler but it should be somelike below

Criteria c1 = session.createCriteria(Candidates.class,candidate);
Criteria j1 = session.createCriteria(Jobs.class,jobs);
c1.setProjection(Property.forName(candName));
j1.setProjection(Property.forName(jobName));
c1.add(Restrictions.and(Property.eqName(candidate.candId,jobs.jobId)));
j1.add(Restrictions.and(jobs.jobName,"job1"));
c1.addCriterion(j1);

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