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!
__________ 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;
}
}
问题内容: 在这种情况下,能否使休眠状态以“正确”的某个值来执行“正确的事情”? 问题是prop是联接表中具有不同表示形式的UserType。在表A中,它表示为整数,在表B中,它表示为char。因此,eq测试转换为看是否1 ==’a’或多或少,这是错误的,但由1或’a’表示的对象应该相同,因此它们应该比较为true。 问题答案: 我认为您可以使用映射文件中关系上的标记来执行此操作。 例如: 我用它
问题内容: 有一种简单的方法可以将hibernate设置为对每个带有postgres的表使用不同的主键ID。我试图在数据源中使用postgres方言: 但这是行不通的。谢谢 问题答案: 简短的答案是没有,没有 简单的 方法可以做到这一点。但是,我找到了一种有效的解决方案。基本上,您需要实现自定义方言。这是一个实现(请在注释中注明实现的原始来源)。 上述实施应当存储为下你的Grails项目中。 接下
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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