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Jpa component primary key and unique key compatible

here are the sql tables:
primary key options - name + value

CREATE TABLE `option` ( id int(11) NOT NULL AUTO_INCREMENT, `name` varchar(45) NOT NULL, `value` varchar(45) NOT NULL, PRIMARY KEY (`name`, `value`), UNIQUE KEY `id_UNIQUE` (`id`) )

primary product key is incremental id

 CREATE TABLE `product` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(50) NOT NULL, PRIMARY KEY (`id`) )

the product has several options (referred to by the unique id key)

 CREATE TABLE product_option ( `id` int(11) NOT NULL AUTO_INCREMENT, `id_product` int(11) NOT NULL, `id_option` int(11) NOT NULL, PRIMARY KEY (`id`), KEY `id_product` (`id_product`), KEY `id_option` (`id_option`), CONSTRAINT `FK_product_option` FOREIGN KEY (`id_product`) REFERENCES `product` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `FK_option_product` FOREIGN KEY (`id_option`) REFERENCES `option` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION )

On the Java side, I matched the "variant" in this way

 @Embeddable public class OptionId implements Serializable{ @Column(name="value") private String value; @Column(name="name") private String name; } @Entity @Table(name="option") public class Option { @Column(name="id", unique=true) @GeneratedValue(strategy=GenerationType.IDENTITY) private Long id; @EmbeddedId private OptionId primaryKey; public OptionId getPrimaryKey() { return primaryKey; } public void setPrimaryKey(OptionId primaryKey) { this.primaryKey = primaryKey; } }

and product in this way

 @Entity @Table(name="product") public class Product { @Id @Column(name="id") @GeneratedValue(strategy=GenerationType.IDENTITY) private Long id; @Column(name="name") private String name @OneToMany(cascade=CascadeType.ALL, fetch=FetchType.LAZY) @JoinTable( name="product_option", joinColumns = @JoinColumn( name="id_product"), inverseJoinColumns = @JoinColumn( name="id_option", referencedColumnName="id") ) private Set<Option> options; }

then at runtime i get this error

 Caused by: java.lang.ArrayIndexOutOfBoundsException: 1 at org.hibernate.sql.SelectFragment.addColumns(SelectFragment.java:107) at org.hibernate.persister.collection.BasicCollectionPersister.manyToManySelectFragment(BasicCollectionPersister.java:308) at org.hibernate.persister.collection.BasicCollectionPersister.selectFragment(BasicCollectionPersister.java:294) at org.hibernate.loader.JoinWalker.selectString(JoinWalker.java:1070) at org.hibernate.loader.AbstractEntityJoinWalker.initStatementString(AbstractEntityJoinWalker.java:124) at org.hibernate.loader.AbstractEntityJoinWalker.initStatementString(AbstractEntityJoinWalker.java:109) at org.hibernate.loader.AbstractEntityJoinWalker.initAll(AbstractEntityJoinWalker.java:91) at org.hibernate.loader.AbstractEntityJoinWalker.initAll(AbstractEntityJoinWalker.java:78) at org.hibernate.loader.entity.CascadeEntityJoinWalker.<init>(CascadeEntityJoinWalker.java:52) at org.hibernate.loader.entity.CascadeEntityLoader.<init>(CascadeEntityLoader.java:47) at org.hibernate.persister.entity.AbstractEntityPersister.createLoaders(AbstractEntityPersister.java:3254) at org.hibernate.persister.entity.AbstractEntityPersister.postInstantiate(AbstractEntityPersister.java:3191) at org.hibernate.persister.entity.SingleTableEntityPersister.postInstantiate(SingleTableEntityPersister.java:728) at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:348) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1872) at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:906) at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:74) at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:225) at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:308) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1477) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1417) ... 60 more

if I remove the "referencedColumnName" of course I get an error

 A Foreign key refering Option from Product has the wrong number of column. should be 2

but I can’t figure out how to fix it.

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Based on your schemes, your face annotations are slightly disabled. If you specify "product" and "option", you should use "id_product" and "id_option":

 @OneToMany(cascade=CascadeType.ALL, fetch=FetchType.LAZY) @JoinTable( name="product_option", joinColumns = @JoinColumn( name="id_product"), inverseJoinColumns = @JoinColumn( name="id_option", referencedColumnName="id") ) private Set<Option> options;

As a side, your life will be much simpler, in the long run, if you switch primary and unique keys in the options table.

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Source: https://habr.com/ru/post/1444153/

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