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  • App engine JPA date query

    - by waney
    Hi There. Assume I have object which represents TASK. Task have due date. How do I create query to get all tasks which are due today? Some working code like "select t from Task t where dueDate=:today" will be usefull. Thank you in advance.

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  • OneToOne JPA / Hibernate eager loading cause N+1 select

    - by Alexandre Lavoie
    I created a method to have multilingual text on different objects without creating field for each languages or tables for each objects types. Now the only problem I've got is N+1 select queries when doing a simple loading. Tables schema : CREATE TABLE `testentities` ( `keyTestEntity` int(11) NOT NULL, `keyMultilingualText` int(11) NOT NULL, PRIMARY KEY (`keyTestEntity`) ) ENGINE=MyISAM AUTO_INCREMENT=0 DEFAULT CHARSET=utf8; CREATE TABLE `common_multilingualtexts` ( `keyMultilingualText` int(11) NOT NULL auto_increment, PRIMARY KEY (`keyMultilingualText`) ) ENGINE=MyISAM AUTO_INCREMENT=0 DEFAULT CHARSET=utf8; CREATE TABLE `common_multilingualtexts_values` ( `languageCode` varchar(5) NOT NULL, `keyMultilingualText` int(11) NOT NULL, `value` text, PRIMARY KEY (`languageCode`,`keyMultilingualText`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; MultilingualText.java @Entity @Table(name = "common_multilingualtexts") public class MultilingualText implements Serializable { private Integer m_iKeyMultilingualText; private Map<String, String> m_lValues = new HashMap<String, String>(); public void setKeyMultilingualText(Integer p_iKeyMultilingualText) { m_iKeyMultilingualText = p_iKeyMultilingualText; } @Id @GeneratedValue @Column(name = "keyMultilingualText") public Integer getKeyMultilingualText() { return m_iKeyMultilingualText; } public void setValues(Map<String, String> p_lValues) { m_lValues = p_lValues; } @ElementCollection(fetch = FetchType.EAGER) @CollectionTable(name = "common_multilingualtexts_values", joinColumns = @JoinColumn(name = "keyMultilingualText")) @MapKeyColumn(name = "languageCode") @Column(name = "value") public Map<String, String> getValues() { return m_lValues; } public void put(String p_sLanguageCode, String p_sValue) { m_lValues.put(p_sLanguageCode,p_sValue); } public String get(String p_sLanguageCode) { if(m_lValues.containsKey(p_sLanguageCode)) { return m_lValues.get(p_sLanguageCode); } return null; } } And it is used like this on a object (having a foreign key to the multilingual text) : @Entity @Table(name = "testentities") public class TestEntity implements Serializable { private Integer m_iKeyEntity; private MultilingualText m_oText; public void setKeyEntity(Integer p_iKeyEntity) { m_iKeyEntity = p_iKeyEntity; } @Id @GeneratedValue @Column(name = "keyEntity") public Integer getKeyEntity() { return m_iKeyEntity; } public void setText(MultilingualText p_oText) { m_oText = p_oText; } @OneToOne(cascade = CascadeType.ALL) @JoinColumn(name = "keyText") public MultilingualText getText() { return m_oText; } } Now, when doing a simple HQL query : from TestEntity, I get a query selecting TestEntity's and one query for each MultilingualText that need to be loaded on each TestEntity. I've searched a lot and found absolutely no solutions. I have tested : @Fetch(FetchType.JOIN) optional = false @ManyToOne instead of @OneToOne Now I am out of idea!

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  • Is it possible to scan Entities in jar files using JPA and hibernate

    - by user1260109
    I have the following situation : Project A - Contains a few entities and is independent Project B - Contains a few entities and is independent Project C - Contains few entities and is dependent on Project A & Project B. I am using Maven to manage dependencies and builds. When I try to test Project A and project B it goes through fine. Each of them has a persistence.xml and a separate persistent context. When I run Project C , It does map any of the entities. I have tried to use the auto-detect, specified the jar file attribute ... but nothing seems to work. It gives me a Mapping Exception saying unknown entity and wont persist or read the Entities from Projects A or B. I have posted the 3 persistence.xml files here. Also, I tried using the class attribute and using the same persistent context but it just wont find the files. Any help is really appreciated. Thanks in advance ! <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0"> <persistence-unit name="A" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect"/> <property name="hibernate.connection.driver_class" value="oracle.jdbc.OracleDriver"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.connection.username" value="username"/> <property name="hibernate.connection.password" value="password"/> <property name="hibernate.connection.url" value="jdbc:oracle:thin:@webdev.epi.web:1521/webdev.world"/> <property name="hibernate.max_fetch_depth" value="3"/> <property name="hibernate.archive.autodetection" value="class"/> </properties> </persistence-unit> </persistence> <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0"> <persistence-unit name="B" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect"/> <property name="hibernate.connection.driver_class" value="oracle.jdbc.OracleDriver"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.connection.username" value="username"/> <property name="hibernate.connection.password" value="password"/> <property name="hibernate.connection.url" value="jdbc:oracle:thin:@webdev.epi.web:1521/webdev.world"/> <property name="hibernate.max_fetch_depth" value="3"/> <property name="hibernate.archive.autodetection" value="class"/> </properties> </persistence-unit> </persistence> <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0"> <persistence-unit name="C" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <jar-file>A-0.0.1-SNAPSHOT.jar</jar-file> <jar-file>B-0.0.1-SNAPSHOT.jar</jar-file> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect"/> <property name="hibernate.connection.driver_class" value="oracle.jdbc.OracleDriver"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.connection.username" value="username"/> <property name="hibernate.connection.password" value="password"/> <property name="hibernate.connection.url" value="jdbc:oracle:thin:@webdev.epi.web:1521/webdev.world"/> <property name="hibernate.max_fetch_depth" value="3"/> <property name="hibernate.archive.autodetection" value="class"/> </properties> </persistence-unit> </persistence>

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  • JPA getSingleResult() or null

    - by Eugene Ramirez
    Hi. I have an insertOrUpdate method which inserts an Entity when it doesn't exist or update it if it does. To enable this, I have to findByIdAndForeignKey, if it returned null insert if not then update. The problem is how do I check if it exists? So I tried getSingleResult. But it throws an exception if the public Profile findByUserNameAndPropertyName(String userName, String propertyName) { String namedQuery = Profile.class.getSimpleName() + ".findByUserNameAndPropertyName"; Query query = entityManager.createNamedQuery(namedQuery); query.setParameter("name", userName); query.setParameter("propName", propertyName); Object result = query.getSingleResult(); if(result==null)return null; return (Profile)result; } but "getSingleResult" throws an exception. Thanks

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  • JPA Secondary Table Issue

    - by Smithers
    I have a three tables: User, Course, and Test. Course has a User foreign key and Test has a Course foreign key. I am having trouble mapping the Test collection for each User since I need an intermediary step from User - Course - Test. I am trying to use a SecondaryTable since the User key for the Test is its associated Course row. Am I on the right track using SecondaryTable or is there a way to use a JoinTable without the inverseJoinColumn?

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  • Calculated property with JPA / Hibernate

    - by Francois
    My Java bean has a childCount property. This property is not mapped to a database column. Instead, it should be calculated by the database with a COUNT() function operating on the join of my Java bean and its children. It would be even better if this property could be calculated on demand / "lazily", but this is not mandatory. In the worst case scenario, I can set this bean's property with HQL or the Criteria API, but I would prefer not to. The Hibernate @Formula annotation may help, but I could barely find any documentation. Any help greatly appreciated. Thanks.

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  • JPA native query join returns object but dereference throws class cast exception

    - by masato-san
    I'm using JPQL Native query to join table and query result is stored in List<Object[]>. public String getJoinJpqlNativeQuery() { String final SQL_JOIN = "SELECT v1.bitbit, v1.numnum, v1.someTime, t1.username, t1.anotherNum FROM MasatosanTest t1 JOIN MasatoView v1 ON v1.username = t1.username;" System.out.println("get join jpql native query is being called ============================"); EntityManager em = null; List<Object[]> out = null; try { em = EmProvider.getDefaultManager(); Query query = em.createNativeQuery(SQL_JOIN); out = query.getResultList(); System.out.println("return object ==========>" + out); System.out.println(out.get(0)); String one = out.get(0).toString(); //LINE 77 where ClassCastException System.out.println(one); } catch(Exception e) { } finally { if(em != null) { em.close; } } } The problem is System.out.println("return object ==========>" + out); outputs: return object ==========> [[true, 0, 2010-12-21 15:32:53.0, masatosan, 0.020], [false, 0, 2010-12-21 15:32:53.0, koga, 0.213]] System.out.println(out.get(0)) outputs: [true, 0, 2010-12-21 15:32:53.0, masatosan, 0.020] So I assumed that I can assign return value of out.get(0) which should be String: String one = out.get(0).toString(); But I get weird ClassCastException. java.lang.ClassCastException: java.util.Vector cannot be cast to [Ljava.lang.Object; at local.test.jaxrs.MasatosanTestResource.getJoinJpqlNativeQuery (MasatosanTestResource.java:77) So what's really going on? Even Object[] foo = out.get(0); would throw an ClassCastException :(

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  • jpa @version optimistic locking

    - by cometta
    I loaded same entity record on 2 separate browser window then press submit (hibernate template.merge), version number incremented for both browser window, but never caught any problem with optimistic lock.. so how to test this? my save() look like this hibernatetemplate().merge(..); setJPAObject(null); //reset after save

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  • Deleting orphans with JPA

    - by homaxto
    I have a one-to-one relation where I use CascadeType.PERSIST. This has over time build up a huge amount of child records that has not been deleted, to such an extend that it is reflected in the performance. Now I wish to add some code that cleans up the database removing all the child records that are not referenced by a parent. At the moment we are talking 400K+ records, at I need to run the code on all customer installations just to be sure they do not run into the same problem. I think the best solution would be to run a named query (because we support two databases) that deletes the necessary records, and this is where I get into problems, because how should I write it in JPQL? The result I want can be defined like the following sql statement, which unfortunaltely does not run on MySQL. DELETE FROM child c1 WHERE c1.pk NOT IN (SELECT DISTINCT p.pk FROM child c2 JOIN parent p ON p.child = c2.pk);

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  • How to setup Eclipselink with JPA?

    - by deamon
    The Eclipselink documentation says that I need the following entries in my pom.xml to get it with Maven: <dependencies> <dependency> <groupId>org.eclipse.persistence</groupId> <artifactId>eclipselink</artifactId> <version>2.0.0</version> <scope>compile</scope> ... </dependency> <dependencies> ... <repositories> <repository> <id>EclipseLink Repo</id> <url>http://www.eclipse.org/downloads/download.php?r=1&amp;nf=1&amp;file=/rt/eclipselink/maven.repo</url> </repository> ... </repositories> But when I try to use @Entity annotation NetBeans tells me, that the class cannot be found. And indeed: there is no Entity class in the javax.persistence package from Eclipselink. How do I have to setup Eclipselink with Maven?

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  • Catching constraint violations in JPA 2.0.

    - by Dennetik
    Consider the following entity class, used with, for example, EclipseLink 2.0.2 - where the link attribute is not the primary key, but unique nontheless. @Entity public class Profile { @Id private Long id; @Column(unique = true) private String link; // Some more attributes and getter and setter methods } When I insert records with a duplicate value for the link attribute, EclipseLink does not throw a EntityExistsException, but throws a DatabaseException, with the message explaining that the unique constraint was violated. This doesn't seem very usefull, as there would not be a simple, database independent, way to catch this exception. What would be the advised way to deal with this? A few things that I have considered are: Checking the error code on the DatabaseException - I fear that this error code, though, is the native error code for the database; Checking the existence of a Profile with the specific value for link beforehand - this obviously would result in an enormous amount of superfluous queries.

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  • JPA concatenating table names for parent/child @OneToMany

    - by Robert
    We are trying to use a basic @OneToMany relationship: @Entity @Table(name = "PARENT_MESSAGE") public class ParentMessage { @Id @Column(name = "PARENT_ID") @GeneratedValue(strategy = GenerationType.IDENTITY) private Integer parentId; @OneToMany(fetch=FetchType.LAZY) private List childMessages; public List getChildMessages() { return this.childMessages; } ... } @Entity @Table(name = "CHILD_MSG_USER_MAP") public class ChildMessage { @Id @Column(name = "CHILD_ID") @GeneratedValue(strategy = GenerationType.IDENTITY) private Integer childId; @ManyToOne(optional=false,targetEntity=ParentMessage.class,cascade={CascadeType.REFRESH}, fetch=FetchType.LAZY) private ParentMessage parentMsg; public ParentMessage getParentMsg() { return parentMsg; } ... } ChildMessage child = new ChildMessage(); em.getTransaction().begin(); ParentMessage parentMessage = (ParentMessage) em.find(ParentMessage.class, parentId); child.setParentMsg(parentMessage); List list = parentMessage.getChildMessages(); if(list == null) list = new ArrayList(); list.add(child); em.getTransaction().commit(); We receive the following error. Why is OpenJPA concatenating the table names to APP.PARENT_MESSAGE_CHILD_MSG_USER_MAP? Of course that table doesn't exist.. the tables defined are APP.PARENT_MESSAGE and APP.CHILD_MSG_USER_MAP Caused by: org.apache.openjpa.lib.jdbc.ReportingSQLException: Table/View 'APP.PARENT_MESSAGE_CHILD_MSG_USER_MAP' does not exist. {SELECT t1.CHILD_ID, t1.PARENT_ID, t1.CREATED_TIME, t1.USER_ID FROM APP.PARENT_MESSAGE_CHILD_MSG_USER_MAP t0 INNER JOIN APP.CHILD_MSG_USER_MAP t1 ON t0.CHILDMESSAGES_CHILD_ID = t1.CHILD_ID WHERE t0.PARENTMESSAGE_PARENT_ID = ?} [code=30000, state=42X05]

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  • Why JPA injection not works on @PersistentUnit

    - by Dewfy
    Hello colleagues! It is continues of question ( http://stackoverflow.com/questions/2570976/struts-2-bean-is-not-created ) I'm using struts2 + toplink in my very simple web application under Tomcat. On the page I would like use iteration tag. That is why I've declared some factory (SomeFactory) that resolves collection of entities (Entity). Per article: http://download-uk.oracle.com/docs/cd/B32110_01/web.1013/b28221/usclient005.htm#CIHCEHHG the only thing I need is declaration: @PersistenceContext(unitName="name_in_persistence_xml") public class SomeFactory { @PersistenceUnit(unitName="name_in_persistence_xml") EntityManagerFactory emf; public EntityManager getEntityManager() { assert(emf != null); //HERE every time it is null return emf.createEntityManager(); } public Collection<Entity> getAll() { return getEntityManager().createNamedQuery("Entity.findAll").getResultList(); } } What is wrong? May be i miss something in web.xml? How to pre-init toplink for web application to allow injection happen?

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  • Are entities cached in jpa by default ?

    - by Nitesh Panchal
    Hello, I add entity to my database and it works fine. But when i retrieve the List, i get the old entity, the new entities i add are not shown until i undeploy the application and redeploy it again. This means are my entities cached by default? But, I haven't made any settings for caching entities in my persistence.xml or any such file. I have even tried calling flush(), refresh() and merge(). But still it shows the old entities only. Am i missing something? Please help me.

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  • JPA 2.0 @OrderColumn annotation in Hibernate 3.5

    - by peperg
    I'm trynig to use @OrderColumn annotation with Hibernate 3.5 @OneToMany(mappedBy = "parent",fetch=FetchType.EAGER, cascade=CascadeType.ALL) @OrderColumn(name = "pos") private List<Children> childrenCollection; When retrieving data everyting works fine. But I can't make it to reorded elements in List and save new order to database.

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  • Remove then Query fails in JPA (deleted entity passed to persist)

    - by nag
    I have two entitys MobeeCustomer and CustomerRegion i want to remove the object from CustomerRegion first Im put join Coloumn in CustomerRegion is null then Remove the Object from the entityManager but Iam getting Exception MobeeCustomer: public class MobeeCustomer implements Serialization{ private Long id; private String custName; private String Address; private String phoneNo; private Set<CustomerRegion> customerRegion = new HashSet<CustomerRegion>(0); @OneToMany(cascade = { CascadeType.PERSIST, CascadeType.REMOVE }, fetch = FetchType.LAZY, mappedBy = "mobeeCustomer") public Set<CustomerRegion> getCustomerRegion() { return CustomerRegion; } public void setCustomerRegion(Set<CustomerRegion> customerRegion) { CustomerRegion = customerRegion; } } CustomerRegion public class CustomerRegion implements Serializable{ private Long id; private String custName; private String description; private String createdBy; private Date createdOn; private String updatedBy; private Date updatedOn; private MobeeCustomer mobeeCustomer; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "MOBEE_CUSTOMER") public MobeeCustomer getMobeeCustomer() { return mobeeCustomer; } public void setMobeeCustomer(MobeeCustomer mobeeCustomer) { this.mobeeCustomer = mobeeCustomer; } } sample code: for (CustomerRegion region : deletedRegionList) { region.setMobeeCustomer(null); getEntityManager().remove(region); } StackTrace: please suggest me how to remove the CustomerRegion Object I am getting Exception javax.persistence.EntityNotFoundException: deleted entity passed to persist: [com.manam.mobee.persist.entity.CustomerRegion#<null>] 15:46:34,614 ERROR [STDERR] at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:613) 15:46:34,614 ERROR [STDERR] at org.hibernate.ejb.AbstractEntityManagerImpl.flush(AbstractEntityManagerImpl.java:299) 15:46:34,614 ERROR [STDERR] at org.jboss.seam.persistence.EntityManagerProxy.flush(EntityManagerProxy.java:92) 15:46:34,614 ERROR [STDERR] at org.jboss.seam.framework.EntityHome.update(EntityHome.java:64)

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  • JPA 2.0 Eclipse Link

    - by Parhs
    Hello... I have this code @Column(updatable=false) @Enumerated(EnumType.STRING) private ExamType examType; How ever i can change the value when i update it via merge.. WHY????

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  • Exception in inserting data into data using JPA in netbeans

    - by sandeep
    SEVERE: Local Exception Stack: Exception [EclipseLink-7092] (Eclipse Persistence Services - 2.0.0.v20091127-r5931): org.eclipse.persistence.exceptions.ValidationException Exception Description: Cannot add a query whose types conflict with an existing query. Query To Be Added: [ReadAllQuery(name="Voter.findAll" referenceClass=Voter jpql="SELECT v FROM Voter v")] is named: [Voter.findAll] with arguments [[]].The existing conflicting query: [ReadAllQuery(name="Voter.findAll" referenceClass=Voter jpql="SELECT v FROM Voter v")] is named: [Voter.findAll] with arguments: [[]].

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  • JPA One to Many using JoinTable Error

    - by user553015
    I am trying to model 1:N (Person & Address) relationship using a junction table (Person_Address). 1.Person (personId PK) 2.Address (addressId PK) 3.PersonAddress ( personId, addressId composite PK, personId FK references Person, addressid FK references Address ) @Entity public class Person { @OneToMany @JoinTable( name="PersonAddress", joinColumns = @JoinColumn( name="personId"), inverseJoinColumns = @JoinColumn( name="addressId") ) public Set<Address> getAddresses() {...} ... } I encounter following error. Not able to find any solution. Caused by: org.hibernate.MappingException: Could not determine type for: com.realestate.details.Address, at table: Person, for columns: [org.hibernate.mapping.Column(address)] at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:269) at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:253) at org.hibernate.mapping.Property.isValid(Property.java:185) at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:440) at org.hibernate.mapping.RootClass.validate(RootClass.java:192) at org.hibernate.cfg.Configuration.validate(Configuration.java:1108) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1293)

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  • How significant are JPA lazy loading performance benefits?

    - by Robert
    I understand that this is highly specific to the concrete application, but I'm just wondering what's the general opinion, or at least some personal experiences on the issue. I have an aversion towards the 'open session in view' pattern, so to avoid it, I'm thinking about simply fetching everything small eagerly, and using queries in the service layer to fetch larger stuff. Has anyone used this and regretted it? And is there maybe some elegant solution to lazy loading in the view layer that I'm not aware of?

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  • How to specify a different column for a @Inheritance JPA annotation

    - by Cue
    @Entity @Inheritance(strategy = InheritanceType.JOINED) public class Foo @Entity @Inheritance(strategy = InheritanceType.JOINED) public class BarFoo extends Foo mysql> desc foo; +---------------+-------------+ | Field | Type | +---------------+-------------+ | id | int | +---------------+-------------+ mysql> desc barfoo; +---------------+-------------+ | Field | Type | +---------------+-------------+ | id | int | | foo_id | int | | bar_id | int | +---------------+-------------+ mysql> desc bar; +---------------+-------------+ | Field | Type | +---------------+-------------+ | id | int | +---------------+-------------+ Is it possible to specify column barfo.foo_id as the joined column? Are you allowed to specify barfoo.id as BarFoo's @Id since you are overriding the getter/seeter of class Foo? I understand the schematics behind this relationship (or at least I think I do) and I'm ok with them. The reason I want an explicit id field for BarFoo is exactly because I want to avoid using a joined key (foo _id, bar _id) when querying for BarFoo(s) or when used in a "stronger" constraint. (as Ruben put it)

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  • Error in inserting data into data using JPA in netbeans

    - by sandeep
    SEVERE: Local Exception Stack: Exception [EclipseLink-7092] (Eclipse Persistence Services - 2.0.0.v20091127-r5931): org.eclipse.persistence.exceptions.ValidationException Exception Description: Cannot add a query whose types conflict with an existing query. Query To Be Added: [ReadAllQuery(name="Voter.findAll" referenceClass=Voter jpql="SELECT v FROM Voter v")] is named: [Voter.findAll] with arguments [[]].The existing conflicting query: [ReadAllQuery(name="Voter.findAll" referenceClass=Voter jpql="SELECT v FROM Voter v")] is named: [Voter.findAll] with arguments: [[]].

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  • Java JPA @OneToMany neededs to reciprocate @ManyToOne?

    - by bguiz
    Create Table A ( ID varchar(8), Primary Key(ID) ); Create Table B ( ID varchar(8), A_ID varchar(8), Primary Key(ID), Foreign Key(A_ID) References A(ID) ); Given that I have created two tables using the SQL statements above, and I want to create Entity classes for them, for the class B, I have these member attributes: @Id @Column(name = "ID", nullable = false, length = 8) private String id; @JoinColumn(name = "A_ID", referencedColumnName = "ID", nullable = false) @ManyToOne(optional = false) private A AId; In class A, do I need to reciprocate the many-to-one relationship? @Id @Column(name = "ID", nullable = false, length = 8) private String id; @OneToMany(cascade = CascadeType.ALL, mappedBy = "AId") private List<B> BList; //<-- Is this attribute necessary? Is it a necessary or a good idea to have a reciprocal @OneToMany for the @ManyToOne? If I make the design decision to leave out the @OneToMany annotated attribute now, will come back to bite me further down.

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  • Unique constraint not created in JPA

    - by homaxto
    I have created the following entity bean, and specified two columns as being unique. Now my problem is that the table is created without the unique constraint, and no errors in the log. Does anyone have an idea? @Entity @Table(name = "cm_blockList", uniqueConstraints = @UniqueConstraint(columnNames = {"terminal", "blockType"})) public class BlockList { @Id @GeneratedValue(strategy = GenerationType.AUTO) private int id; @ManyToOne(cascade = CascadeType.PERSIST) @JoinColumn(name="terminal") private Terminal terminal; @Enumerated(EnumType.STRING) private BlockType blockType; private String regEx; }

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