Hibernate why is creating n query instead of 1?

Question

Hy I want to load all jobSeekers from JobSeeker table with a single query and with criteria, and hibernate instead of writing 1 query it write n query for n JobSeeker, and I dont have idea why please help. This is my JobSeeker class:

@Entity
@Table(name="JOB_SEEKER") 
public class JobSeeker extends BaseEntity{

@Column(name = "name", length = 128, nullable = false)
@Expose
private String name;

@OneToOne
@JoinColumn(name = "user_id")
private User user;

.
.
.

This is my User class:

 @Entity
 @Table(name="USER_AUTH")
 public class User extends BaseEntity {

 @Column(name = "username", nullable = false, length = 64, unique = true)
 @Size(max=64)
 @Expose
 @NotEmpty
 private String username;

 @Column(name = "password", nullable = false, length = 64)
 @Size(min=6,max=64)
 private String password;

 @OneToOne(mappedBy = "user", cascade=CascadeType.ALL)
 private UserSettings userSettings;


 @OneToOne(mappedBy = "user", fetch = FetchType.LAZY, cascade=CascadeType.ALL)
 @Fetch(FetchMode.SELECT)
 private JobSeeker jobSeeker;
.
.
.

And userSettings class:

@Entity
@Table(name="USER_SETTINGS") 
public class UserSettings extends BaseEntity{

@OneToOne
@JoinColumn(name = "user_id")   
@Expose
private User user;
.
.
.

And my findAll select:

Session session = getCurrentSession();

Criteria criteria = session.createCriteria(JobSeeker.class, "jobSeeker")
        .setFirstResult(dataTableFilter.iDisplayStart)
        .setMaxResults(dataTableFilter.iDisplayLength);
List<?> list = new ArrayList();
list = criteria.list();

And it makes this querys:

Hibernate: select this_.ID as ID1_16_3_, this_.CREATED_BY as CREATED_2_16_3_, this_.CREATED_DATE as CREATED_3_16_3_, this_.MODIFIED_BY as MODIFIED4_16_3_, this_.MODIFIED_DATE as MODIFIED5_16_3_, this_.VERSION as VERSION6_16_3_, this_.adress as adress7_16_3_, this_.city as city8_16_3_, this_.forgot_password as forgot_p9_16_3_, this_.time_forgot_password as time_fo10_16_3_, this_.name as name11_16_3_, this_.not_seen as not_see12_16_3_, this_.phone as phone13_16_3_, this_.picture_path as picture14_16_3_, this_.user_id as user_id15_16_3_, user2_.ID as ID1_26_0_, user2_.CREATED_BY as CREATED_2_26_0_, user2_.CREATED_DATE as CREATED_3_26_0_, user2_.MODIFIED_BY as MODIFIED4_26_0_, user2_.MODIFIED_DATE as MODIFIED5_26_0_, user2_.VERSION as VERSION6_26_0_, user2_.email as email7_26_0_, user2_.facebook_id as facebook8_26_0_, user2_.hash_code as hash_cod9_26_0_, user2_.linkedin_id as linkedi10_26_0_, user2_.password as passwor11_26_0_, user2_.role_id as role_id15_26_0_, user2_.status as status12_26_0_, user2_.twitter_id as twitter13_26_0_, user2_.username as usernam14_26_0_, role3_.ID as ID1_22_1_, role3_.CREATED_BY as CREATED_2_22_1_, role3_.CREATED_DATE as CREATED_3_22_1_, role3_.MODIFIED_BY as MODIFIED4_22_1_, role3_.MODIFIED_DATE as MODIFIED5_22_1_, role3_.VERSION as VERSION6_22_1_, role3_.description as descript7_22_1_, role3_.name as name8_22_1_, usersettin4_.ID as ID1_27_2_, usersettin4_.CREATED_BY as CREATED_2_27_2_, usersettin4_.CREATED_DATE as CREATED_3_27_2_, usersettin4_.MODIFIED_BY as MODIFIED4_27_2_, usersettin4_.MODIFIED_DATE as MODIFIED5_27_2_, usersettin4_.VERSION as VERSION6_27_2_, usersettin4_.last_news_send_date as last_new7_27_2_, usersettin4_.preferred_language as preferre8_27_2_, usersettin4_.recieve_newsletter as recieve_9_27_2_, usersettin4_.user_id as user_id10_27_2_ from JOB_SEEKER this_ left outer join USER_AUTH user2_ on this_.user_id=user2_.ID left outer join ROLE role3_ on user2_.role_id=role3_.ID left outer join USER_SETTINGS usersettin4_ on user2_.ID=usersettin4_.user_id order by this_.name asc
Hibernate: select jobseeker0_.ID as ID1_16_3_, jobseeker0_.CREATED_BY as CREATED_2_16_3_, jobseeker0_.CREATED_DATE as CREATED_3_16_3_, jobseeker0_.MODIFIED_BY as MODIFIED4_16_3_, jobseeker0_.MODIFIED_DATE as MODIFIED5_16_3_, jobseeker0_.VERSION as VERSION6_16_3_, jobseeker0_.adress as adress7_16_3_, jobseeker0_.city as city8_16_3_, jobseeker0_.forgot_password as forgot_p9_16_3_, jobseeker0_.time_forgot_password as time_fo10_16_3_, jobseeker0_.name as name11_16_3_, jobseeker0_.not_seen as not_see12_16_3_, jobseeker0_.phone as phone13_16_3_, jobseeker0_.picture_path as picture14_16_3_, jobseeker0_.user_id as user_id15_16_3_, user1_.ID as ID1_26_0_, user1_.CREATED_BY as CREATED_2_26_0_, user1_.CREATED_DATE as CREATED_3_26_0_, user1_.MODIFIED_BY as MODIFIED4_26_0_, user1_.MODIFIED_DATE as MODIFIED5_26_0_, user1_.VERSION as VERSION6_26_0_, user1_.email as email7_26_0_, user1_.facebook_id as facebook8_26_0_, user1_.hash_code as hash_cod9_26_0_, user1_.linkedin_id as linkedi10_26_0_, user1_.password as passwor11_26_0_, user1_.role_id as role_id15_26_0_, user1_.status as status12_26_0_, user1_.twitter_id as twitter13_26_0_, user1_.username as usernam14_26_0_, role2_.ID as ID1_22_1_, role2_.CREATED_BY as CREATED_2_22_1_, role2_.CREATED_DATE as CREATED_3_22_1_, role2_.MODIFIED_BY as MODIFIED4_22_1_, role2_.MODIFIED_DATE as MODIFIED5_22_1_, role2_.VERSION as VERSION6_22_1_, role2_.description as descript7_22_1_, role2_.name as name8_22_1_, usersettin3_.ID as ID1_27_2_, usersettin3_.CREATED_BY as CREATED_2_27_2_, usersettin3_.CREATED_DATE as CREATED_3_27_2_, usersettin3_.MODIFIED_BY as MODIFIED4_27_2_, usersettin3_.MODIFIED_DATE as MODIFIED5_27_2_, usersettin3_.VERSION as VERSION6_27_2_, usersettin3_.last_news_send_date as last_new7_27_2_, usersettin3_.preferred_language as preferre8_27_2_, usersettin3_.recieve_newsletter as recieve_9_27_2_, usersettin3_.user_id as user_id10_27_2_ from JOB_SEEKER jobseeker0_ left outer join USER_AUTH user1_ on jobseeker0_.user_id=user1_.ID left outer join ROLE role2_ on user1_.role_id=role2_.ID left outer join USER_SETTINGS usersettin3_ on user1_.ID=usersettin3_.user_id where jobseeker0_.user_id=?
Hibernate: select jobseeker0_.ID as ID1_16_3_, jobseeker0_.CREATED_BY as CREATED_2_16_3_, jobseeker0_.CREATED_DATE as CREATED_3_16_3_, jobseeker0_.MODIFIED_BY as MODIFIED4_16_3_, jobseeker0_.MODIFIED_DATE as MODIFIED5_16_3_, jobseeker0_.VERSION as VERSION6_16_3_, jobseeker0_.adress as adress7_16_3_, jobseeker0_.city as city8_16_3_, jobseeker0_.forgot_password as forgot_p9_16_3_, jobseeker0_.time_forgot_password as time_fo10_16_3_, jobseeker0_.name as name11_16_3_, jobseeker0_.not_seen as not_see12_16_3_, jobseeker0_.phone as phone13_16_3_, jobseeker0_.picture_path as picture14_16_3_, jobseeker0_.user_id as user_id15_16_3_, user1_.ID as ID1_26_0_, user1_.CREATED_BY as CREATED_2_26_0_, user1_.CREATED_DATE as CREATED_3_26_0_, user1_.MODIFIED_BY as MODIFIED4_26_0_, user1_.MODIFIED_DATE as MODIFIED5_26_0_, user1_.VERSION as VERSION6_26_0_, user1_.email as email7_26_0_, user1_.facebook_id as facebook8_26_0_, user1_.hash_code as hash_cod9_26_0_, user1_.linkedin_id as linkedi10_26_0_, user1_.password as passwor11_26_0_, user1_.role_id as role_id15_26_0_, user1_.status as status12_26_0_, user1_.twitter_id as twitter13_26_0_, user1_.username as usernam14_26_0_, role2_.ID as ID1_22_1_, role2_.CREATED_BY as CREATED_2_22_1_, role2_.CREATED_DATE as CREATED_3_22_1_, role2_.MODIFIED_BY as MODIFIED4_22_1_, role2_.MODIFIED_DATE as MODIFIED5_22_1_, role2_.VERSION as VERSION6_22_1_, role2_.description as descript7_22_1_, role2_.name as name8_22_1_, usersettin3_.ID as ID1_27_2_, usersettin3_.CREATED_BY as CREATED_2_27_2_, usersettin3_.CREATED_DATE as CREATED_3_27_2_, usersettin3_.MODIFIED_BY as MODIFIED4_27_2_, usersettin3_.MODIFIED_DATE as MODIFIED5_27_2_, usersettin3_.VERSION as VERSION6_27_2_, usersettin3_.last_news_send_date as last_new7_27_2_, usersettin3_.preferred_language as preferre8_27_2_, usersettin3_.recieve_newsletter as recieve_9_27_2_, usersettin3_.user_id as user_id10_27_2_ from JOB_SEEKER jobseeker0_ left outer join USER_AUTH user1_ on jobseeker0_.user_id=user1_.ID left outer join ROLE role2_ on user1_.role_id=role2_.ID left outer join USER_SETTINGS usersettin3_ on user1_.ID=usersettin3_.user_id where jobseeker0_.user_id=?
.
.

I tried to put in JobSeeker class @OneToOne(fetch = FetchType.LAZY) with this write just one query, but for example in findOne() gives no proxy session for user, did not load the user and I need it. In findAll I need just the JobSeeker without user. I would write the select with hibernate.query but I need to do with criteria. Anyone can help me?

UPDATE: Generic class:

public abstract class AbstractHibernateDao<T extends BaseEntity, PK extends Serializable> implements IOperations<T, PK> {

    private Class<T> clazz;
    private Class<PK> pkClazz;

    @Autowired
    private SessionFactory sessionFactory;


    protected final void setClazz(final Class<T> clazzToSet, final Class<PK> plClazzToSet) {
        clazz = Preconditions.checkNotNull(clazzToSet);
        pkClazz = Preconditions.checkNotNull(plClazzToSet);
    }

    @Override
    public final T findOne(final PK id) {
        return (T) getCurrentSession().get(clazz, id);
    }

UPDATE If fetchType lazy it goes good on findAll writes just one query

@OneToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "user_id")
private User user;

but gives this error on jobSeekerService.findOne(id) :

SEVERE: Servlet.service() for servlet [spring-mvc-dispatcher] in context with path [/ProiectName] threw exception [Request processing failed; nested exception is org.apache.tiles.request.render.CannotRenderException: ServletException including path '/WEB-INF/views/layout/adminLayout.jsp'.] with root cause
org.hibernate.LazyInitializationException: could not initialize proxy - no Session
    at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:165)
    at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:286)
    at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:185)
    at com.proiect.hrms.persistence.model.User_$$_jvstd45_a.getEmail(User_$$_jvstd45_a.java)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at javax.el.BeanELResolver.getValue(BeanELResolver.java:87)
    at org.apache.jasper.el.JasperELResolver.getValue(JasperELResolver.java:104)
    at org.apache.el.parser.AstValue.getValue(AstValue.java:183)
    at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:185)
    at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:1026)
    at org.apache.jsp.WEB_002dINF.views.admin.main.candidates.details_jsp._jspService(details_jsp.java:143)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:605)
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:544)
    at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:954)
    at org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:684)
    at org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:678)
    at org.apache.tiles.request.jsp.JspRequest.doInclude(JspRequest.java:123)
    at org.apache.tiles.request.AbstractViewRequest.dispatch(AbstractViewRequest.java:47)
    at org.apache.tiles.request.render.DispatchRenderer.render(DispatchRenderer.java:47)
    at org.apache.tiles.request.render.ChainedDelegateRenderer.render(ChainedDelegateRenderer.java:68)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:259)
    at org.apache.tiles.template.InsertAttributeModel.renderAttribute(InsertAttributeModel.java:188)
    at org.apache.tiles.template.InsertAttributeModel.execute(InsertAttributeModel.java:132)
    at org.apache.tiles.jsp.taglib.InsertAttributeTag.doTag(InsertAttributeTag.java:299)
    at org.apache.jsp.WEB_002dINF.views.layout.adminLayout_jsp._jspx_meth_tiles_005finsertAttribute_005f3(adminLayout_jsp.java:304)
    at org.apache.jsp.WEB_002dINF.views.layout.adminLayout_jsp._jspService(adminLayout_jsp.java:187)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:487)
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:412)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:339)
    at org.apache.tiles.request.servlet.ServletRequest.forward(ServletRequest.java:265)
    at org.apache.tiles.request.servlet.ServletRequest.doForward(ServletRequest.java:228)
    at org.apache.tiles.request.AbstractClientRequest.dispatch(AbstractClientRequest.java:57)
    at org.apache.tiles.request.render.DispatchRenderer.render(DispatchRenderer.java:47)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:259)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:397)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:238)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:221)
    at org.apache.tiles.renderer.DefinitionRenderer.render(DefinitionRenderer.java:59)
    at org.springframework.web.servlet.view.tiles3.TilesView.renderMergedOutputModel(TilesView.java:114)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:303)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1228)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1011)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:955)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:154)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:199)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:110)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:50)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:662)

yo should google about n+1 issue in hibernate and every orm. There are ways to tune up it. — Jean Cedron, Jul 15 '15 at 15:14
that was the first thing what I do, but I did not get any solution for my problem, thats why I come here and ask it — FAndrew, Jul 16 '15 at 07:20

score 2 · Accepted Answer · edited May 23 '17 at 11:51

2

Just replace your specific piece of code with following code and you are done.

@OneToOne(mappedBy = "user", fetch = FetchType.LAZY, optional = false, cascade=CascadeType.ALL)
 @Fetch(FetchMode.JOIN)
 private JobSeeker jobSeeker;

See, I have just changed FetchMode.JOIN instead of FetchMode.SELECT.

From Hibernate docs,

SELECT : use a select for each individual entity, collection, or join load

For more details please refer : Hibernate Docs.

UPDATE : By default hibernate's behavior is like this for fetching strategy which is also playing role here,

OneToMany: LAZY
ManyToOne: EAGER
ManyToMany: LAZY
OneToOne: EAGER

To overcome this you just need to update your OneToOne mapping in JobSeaker class like this,

@OneToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "user_id")
private User user;

Refer : Use of Optional flag.

UPDATE : Now we have disabled default behavior of eager loading of hibernate. So we need to trigger hibernate to load data using join query like this,

Session session = getCurrentSession(); 

Criteria criteria = session.createCriteria(JobSeeker.class, "jobSeeker")
        .createAlias("jobSeeker.user","user") //default inner join
        .setFirstResult(dataTableFilter.iDisplayStart)
        .setMaxResults(dataTableFilter.iDisplayLength);
List<?> list = new ArrayList();
list = criteria.list();

edited May 23 '17 at 11:51

Community

1
1

answered Jul 14 '15 at 12:46

Vishal Zanzrukia

4,378
3
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I changed and gives the same querys. – FAndrew Jul 14 '15 at 12:55
which version of Hibernate are you using? – Vishal Zanzrukia Jul 14 '15 at 13:00
4.3.6.Final - version – FAndrew Jul 14 '15 at 13:02
I think you wanted to write my JobSeeker class to update like that, but if I do it is good but if I use my generic function findOne(id) see Updated question then gives no proxy session for user. And I shoud get from JobSeeker object the User object after a findOne(id). – FAndrew Jul 14 '15 at 13:21
If I add this @OneToOne(fetch = FetchType.LAZY) then when I use the findOne(id) generic function gives no proxy session, I also tried .setFetchMode("user",FetchMode.LAZY) and now it make for each jobSeeker a user select, and without "user", how you write you gives this error The method setFetchMode(String, FetchMode) in the type Criteria is not applicable for the arguments (FetchMode) ,and I dont have setFetchMode(FetchMode) – FAndrew Jul 14 '15 at 13:38
nope same no proxy session on findOne jobSeeker, can`t load the user, I writed in update the error check it – FAndrew Jul 16 '15 at 07:25
Did not load the user object in jobSeeker I saw this error on user object: com.sun.jdi.InvocationException occurred invoking method. – FAndrew Jul 16 '15 at 08:29
1

Yes man, thank you very much for this help, the last update solved my problem now writes just one query. :) – FAndrew Jul 17 '15 at 06:12

Hibernate why is creating n query instead of 1?

1 Answers1