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Hibernate和PostgreSQL中具有UserType的数组-> MappingException

赏高格
2023-03-14
问题内容

我创建了一个新的Spring Roo项目只是为了对其进行测试。这是不同的文件(所有Java类都位于包测试中):

persistence.xml

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
  <persistence-unit name="persistenceUnit" transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <properties>
    <!--  <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/> -->
    <property name="hibernate.dialect" value="test.PostgreSQLDialectArray"/>
    <!-- value="create" to build a new database on each run; value="update" to modify an existing database; value="create-drop" means the same as "create" but also drops tables when Hibernate closes; value="validate" makes no changes to the database -->
    <property name="hibernate.hbm2ddl.auto" value="create"/>
    <property name="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy"/>
    <property name="hibernate.connection.charSet" value="UTF-8"/>
    <!-- Uncomment the following two properties for JBoss only -->
    <!-- property name="hibernate.validator.apply_to_ddl" value="false" /-->
    <!-- property name="hibernate.validator.autoregister_listeners" value="false" /-->
    </properties>
  </persistence-unit>
</persistence>

TestArray.java

package test;

import java.math.BigInteger;
import java.security.SecureRandom;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.roo.addon.javabean.RooJavaBean;
import org.springframework.roo.addon.serializable.RooSerializable;
import org.springframework.roo.addon.tostring.RooToString;

@RooJavaBean
@RooToString
@RooSerializable
public class TestArray {


     private static final long serialVersionUID = 1L;
     private SecureRandom random = new SecureRandom();


     public String nextSessionId()
     {
         return new BigInteger(130, random).toString(32);
     }

     public static void main(String[] args) {
         ApplicationContext context;
 context = new ClassPathXmlApplicationContext("classpath:META-INF/spring/applicationContext.xml");
         int[] array = new int[1428];
         TestArray test = new TestArray();
         Blabla blabla = new Blabla();
         int nb = 1428;

         for(int i = 0 ; i < nb ; i++)
         array[i] = test.random.nextInt();

          //         blabla.setTest(array);
          //         blabla.persist();
          //        System.out.println(Arrays.toString(blabla.getTest()));

         System.out.println(java.sql.Types.ARRAY);
         System.out.println("Done");
     }
}

Blabla.java

package test;

import org.hibernate.annotations.Type;
import org.springframework.roo.addon.entity.RooEntity;
import org.springframework.roo.addon.javabean.RooJavaBean;
import org.springframework.roo.addon.tostring.RooToString;

@RooJavaBean
@RooToString
@RooEntity
public class Blabla {

    @Type(type = "test.IntArrayUserType")
    private int[] array;
}

PostgreSQLDialectArray

package test;

import java.sql.Types;


public class PostgreSQLDialectArray extends org.hibernate.dialect.PostgreSQLDialect{

    public PostgreSQLDialectArray() { 
        super(); 
        registerHibernateType(Types.ARRAY, "array"); 
    }
 }

IntArrayUserType.java(与使用hibernate映射postgres数组基本相同)

package test;
import java.io.Serializable;
import java.sql.Array;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.hibernate.HibernateException;
import org.hibernate.usertype.UserType;



public class IntArrayUserType implements UserType {

    protected static final int  SQLTYPE = java.sql.Types.ARRAY;

    private int[] toPrimitive(Integer[] array){
        int[] a = new int[array.length];
        for(int i = 0 ; i < array.length ; i++)
            a[i] = array[i];
        return a;
    }

    private Integer[] toObject(int[] array){
        Integer[] a = new Integer[array.length];
        for(int i = 0 ; i < array.length ; i++)
            a[i] = array[i];
        return a;
    }

    @Override
    public Object nullSafeGet(final ResultSet rs, final String[] names, final Object owner) throws HibernateException, SQLException {
        Array array = rs.getArray(names[0]);
        Integer[] javaArray = (Integer[]) array.getArray();
        return toPrimitive(javaArray);
    }

    @Override
    public void nullSafeSet(final PreparedStatement statement, final Object object, final int i) throws HibernateException, SQLException {
        System.out.println("test null safe set...");
        Connection connection = statement.getConnection();

        int[] castObject = (int[]) object;
        Integer[] integers = toObject(castObject);
        Array array = connection.createArrayOf("integer", integers);

        statement.setArray(i, array);
        System.out.println("test null safe set...");
    }

    @Override
    public Object assemble(final Serializable cached, final Object owner) throws HibernateException {
        return cached;
    }

    @Override
    public Object deepCopy(final Object o) throws HibernateException {
        return o == null ? null : ((int[]) o).clone();
    }

    @Override
    public Serializable disassemble(final Object o) throws HibernateException {
        return (Serializable) o;
    }

    @Override
    public boolean equals(final Object x, final Object y) throws HibernateException {
        return x == null ? y == null : x.equals(y);
    }

    @Override
    public int hashCode(final Object o) throws HibernateException {
        return o == null ? 0 : o.hashCode();
    }

    @Override
    public boolean isMutable() {
        return false;
    }

    @Override
    public Object replace(final Object original, final Object target, final Object owner) throws HibernateException {
        return original;
    }

    @Override
    public Class<int[]> returnedClass() {
        return int[].class;
    }

    @Override
    public int[] sqlTypes() {
        return new int[] { SQLTYPE };
    }
}

现在,堆栈跟踪:

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager' defined in class path resource [META-INF/spring/applicationContext.xml]: Cannot resolve reference to bean 'entityManagerFactory' while setting bean property 'entityManagerFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [META-INF/spring/applicationContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: persistenceUnit] Unable to build EntityManagerFactory
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:106)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1325)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1086)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
at test.TestArray.main(TestArray.java:29)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [META-INF/spring/applicationContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: persistenceUnit] Unable to build EntityManagerFactory
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1420)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:322)
... 15 more
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: persistenceUnit] Unable to build EntityManagerFactory
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915)
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)
... 22 more
Caused by: org.hibernate.MappingException: No Dialect mapping for JDBC type: 2003
at org.hibernate.dialect.TypeNames.get(TypeNames.java:77)
at org.hibernate.dialect.TypeNames.get(TypeNames.java:100)
at org.hibernate.dialect.Dialect.getTypeName(Dialect.java:296)
at org.hibernate.mapping.Column.getSqlType(Column.java:208)
at org.hibernate.mapping.Table.sqlCreateString(Table.java:418)
at org.hibernate.cfg.Configuration.generateSchemaCreationScript(Configuration.java:1099)
at org.hibernate.tool.hbm2ddl.SchemaExport.<init>(SchemaExport.java:106)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:372)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1872)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:906)
... 27 more

因此,我猜我创建的方言根本没有使用或说错了,但我不知道为什么。我认为@Type批注应该进行映射,但是我已经看到了一些标签,但是我不知道此示例中是否需要它们,如果需要,我在哪里放置它们?我被这个问题困扰了已经两天了,我感到绝望。你能帮我调试这个程序吗?请。提前非常感谢你。

编辑0:

persistence.xml文件似乎找到了正确的方言,但是在执行registerHibernateType(Types.ARRAY,“ array”)之后,函数getTypeName(2003)抛出上述错误。顺便说一句,我正在使用Hibernate 3.6.4.Final和postgresql 8.4-702.jdbc3。

编辑1:

我将以下行添加到PostgreSQLDialectArray构造函数中:

registerColumnType(Types.ARRAY, "integer[$l]" ); 

这似乎可以部分解决问题。但是,现在出现另一个错误:

2019-01-09 11:14:30,281 [main] ERROR org.hibernate.tool.hbm2ddl.SchemaExport - Unsuccessful: create table blabla (id int8 not null, array int[255], name varchar(255), test int4 not null, version int4, primary key (id))
2019-01-09 11:14:30,282 [main] ERROR org.hibernate.tool.hbm2ddl.SchemaExport - ERREUR: erreur de syntaxe sur ou près de « array »
  Position: 40

显然,hibernate仍然不知道如何创建一个带有数组的表…

编辑2:

似乎postgresql不喜欢我的列称为“数组”的事实。我改变了,它奏效了。该表是由hibernate的整数数组创建的。

但是由于UserType实施中的问题,我无法使用hibernate保存任何数组。显然,创建数组失败,并带有createArrayOf。我正在阅读一些有关此问题的线程,告诉它们访问基础连接而不是包装器。我想我要打开一个新线程链接到此线程,因为这个问题完全不同。

堆栈跟踪:

Exception in thread "main" java.lang.AbstractMethodError: org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.createArrayOf(Ljava/lang/String;[Ljava/lang/Object;)Ljava/sql/Array;
at test.IntArrayUserType.nullSafeSet(IntArrayUserType.java:59)
at org.hibernate.type.CustomType.nullSafeSet(CustomType.java:140)
at org.hibernate.persister.entity.AbstractEntityPersister.dehydrate(AbstractEntityPersister.java:2184)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2430)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2874)
at org.hibernate.action.EntityInsertAction.execute(EntityInsertAction.java:79)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:265)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:184)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133)
at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:76)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:467)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393)
at org.springframework.transaction.aspectj.AbstractTransactionAspect.ajc$afterReturning$org_springframework_transaction_aspectj_AbstractTransactionAspect$3$2a73e96c(AbstractTransactionAspect.aj:78)
at test.Blabla_Roo_Entity.ajc$interMethod$test_Blabla_Roo_Entity$test_Blabla$persist(Blabla_Roo_Entity.aj:56)
at test.Blabla.persist(Blabla.java:1)
at test.Blabla_Roo_Entity.ajc$interMethodDispatch1$test_Blabla_Roo_Entity$test_Blabla$persist(Blabla_Roo_Entity.aj)
at test.TestArray.main(TestArray.java:39)

编辑3:

最后,进行以下修改后,整数数组的UserType起作用:

将以下行添加到applicationContext.xml中:

<bean class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" id="dataSource">
....
<property name="accessToUnderlyingConnectionAllowed" value="true" />
</bean>

从IntArrayUserType修改nullSafeSet

    @Override
    public void nullSafeSet(final PreparedStatement statement, final Object object, final int i) throws HibernateException, SQLException {
        Connection connection = statement.getConnection();
        int[] castObject = (int[]) object;
        Integer[] integers = toObject(castObject);
        Connection conn = ((DelegatingConnection) connection).getInnermostDelegate();
        Array array = conn.createArrayOf("integer", integers);
        statement.setArray(i, array);
    }

但是从表blabla获取所有条目时仍然存在问题:函数findAllBlablas无法正常工作,仅返回第一个条目…

编辑4:

实际上,它工作得很好,但是eclipse控制台无法打印所有数据。就这样!


问题答案:
__________ HibernateSessionFactory.xml ___________________________

    <property name="hibernateProperties">
        <props>
            <!-- <prop key="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</prop> -->
            <prop key="hibernate.dialect">com.test.model.PostgreSQLDialectArray</prop>              
            <prop key="hibernate.show_sql">true</prop>
            <prop key="hibernate.format_sql">true</prop>
            <prop key="hibernate.generate_statistics">false</prop>
            <prop key="hibernate.connection.pool_size">10</prop>
            <prop key="hibernate.archive.autodetection">class</prop>
            <prop key="hibernate.hbm2ddl.auto">create</prop>                
            <prop key="cache.provider_class">org.hibernate.cache.NoCacheProvider</prop>
        </props>
    </property>



    ______________ PostgreSQLDialectArray.java _______________________


package com.test.model;

import java.sql.Types;

public class PostgreSQLDialectArray extends org.hibernate.dialect.PostgreSQL82Dialect{

    public PostgreSQLDialectArray() {

        super();    

        System.out.println("Register Hibernate Type ... ");
        registerHibernateType(Types.ARRAY, "array");

        System.out.println("Register Column Type ... ");
        registerColumnType(Types.ARRAY, "integer[]");

    }
}



_____________ CustomArrayType.java ______________________________


package com.test.model;

import java.io.Serializable;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.sql.Array;

import org.hibernate.*;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.usertype.UserType;

 public class CustomArrayType implements UserType
 {

     protected static final int  SQLTYPE = java.sql.Types.ARRAY;

     private int[] toPrimitive(Integer[] array){
         int[] a = new int[array.length];
         for(int i = 0 ; i < array.length ; i++)
             a[i] = array[i];
         return a;
     }

     private Integer[] toObject(int[] array){
         Integer[] a = new Integer[array.length];
         for(int i = 0 ; i < array.length ; i++)
             a[i] = array[i];
         return a;
     }

     @Override
     public Object nullSafeGet(final ResultSet rs, final String[] names, SessionImplementor session, final Object owner) throws HibernateException, SQLException {
         Array array = rs.getArray(names[0]);
         Integer[] javaArray = (Integer[]) array.getArray();
         return toPrimitive(javaArray);
     }

     @Override
     public void nullSafeSet(final PreparedStatement statement, final Object object, final int i, SessionImplementor session) throws HibernateException, SQLException {
         System.out.println("test null safe set...");
         Connection connection = statement.getConnection();

         int[] castObject = (int[]) object;
         Integer[] integers = toObject(castObject);
         Array array = connection.createArrayOf("integer", integers);

         statement.setArray(i, array);
         System.out.println("test null safe set...");
     }

     @Override
     public Object assemble(final Serializable cached, final Object owner) throws HibernateException {
         return cached;
     }

     @Override
     public Object deepCopy(final Object o) throws HibernateException {
         return o == null ? null : ((int[]) o).clone();
     }

     @Override
     public Serializable disassemble(final Object o) throws HibernateException {
         return (Serializable) o;
     }

     @Override
     public boolean equals(final Object x, final Object y) throws HibernateException {
         return x == null ? y == null : x.equals(y);
     }

     @Override
     public int hashCode(final Object o) throws HibernateException {
         return o == null ? 0 : o.hashCode();
     }

     @Override
     public boolean isMutable() {
         return false;
     }

     @Override
     public Object replace(final Object original, final Object target, final Object owner) throws HibernateException {
         return original;
     }

     @Override
     public Class<int[]> returnedClass() {
         return int[].class;
     }

     @Override
     public int[] sqlTypes() {
         return new int[] { SQLTYPE };
     }

}



____________ MyClass.java ___________________________

package com.test.model;

import static javax.persistence.GenerationType.IDENTITY;

import java.io.Serializable;
import java.sql.Time;
import java.sql.Timestamp;
import java.sql.Types;
import java.util.Date;
import java.util.List;
import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import org.hibernate.annotations.Type;

@Entity
@Table(name = "MyClass")
public class MyClass implements Serializable {

    private static final long serialVersionUID = -2520209406925143850L;

    @Id
    @GeneratedValue(strategy = IDENTITY)
    private Long id;

    @Type(type = "com.test.model.CustomArrayType")
    @Column(name = "arrayDay", nullable = true)
    private int[] arrayDay;           

    public Long getId() {
    return id;
    }

    public void setId(Long id) {
    this.id = id;
    }

    public int[] getArrayDay() {
        return arrayDay;
    }

    public void setArrayDay(int[] arrayDay) {
        this.arrayDay = arrayDay;
    }  

}



______________ ArrayTypeTests.java ___________________________



package com.test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.test.model.MyClass;
import com.test.service.MyClassService;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "classpath:application-context.xml" })
public class ArrayTypeTests implements ApplicationContextAware {

    @Autowired
    private MyClassService myClassService;

    public static ApplicationContext ctx;

    @Test
    public void test_() {
       System.out.println("Test junit");
    }

    @Test
    public void test_arrayDays() {

    System.out.println("\n - Start test_array - ");
    MyClass myClass = myClassService.getMyClassById(1L);
    if (myClass != null) {
        int[] array = myClass.getArrayDay();
        System.out.println("\n valor1:" + array[0]);
        System.out.println("\n valor2:" + array[1]);
        System.out.println("\n\n test_array OK ");
    } else {
        System.out.println("\n ERROR");
    }
    System.out.println("\n - End test_array - ");

    }

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
    ctx = applicationContext;
    }

}


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  • 问题内容: 我在PostgreSQL类型上使用%%运算符,该运算符将hstore(有效键值类型)转换为元素交替为{{key,value},{key value}}的数组。 当我想返回这些平坦的hstore的数组时,出现此错误:由于PostgreSQL缺乏对数组数组的支持。 从好奇心的角度来看,有人知道为什么不支持这些吗?更重要的是,这种情况是否可以解决? 目前,我将结果串联成一个字符串(用逗号分隔

  • 问题内容: 我使用Vlad Mihalcea的库来将SQL数组(在我的情况下为Postgresql)映射到JPA。然后,假设我有一个实体,例如。 适当的SQL是: 使用QueryDSL,我想获取包含所有给定标签的行。原始SQL可能是: (摘自:https : //www.postgresql.org/docs/9.1/static/functions- array.html ) 可以用QueryD

  • 每个租户都有自己的数据库,可以更详细地处理用户,并且需要有一个中央数据库来处理: 代币(OAuth2) 我已经找到了多租户的解决方案,它允许我根据用户确定数据源。然而,我不确定如何将某些crud存储库链接到这个中心数据源,而将其他存储库链接到可变数据源。 另一个解决方案涉及更新属性文件,并使用配置服务器(即通过git)来触发@ReresScope注释配置。虽然我不确定这是否适用于数据源,或者这是否