Я использую hbmddl.auto для создания в файле конфигурации hibernate и использую его для подключения к базе данных derby в сетевом режиме (не встроено, не знаю, актуально ли это).
Вот мой hibernate.cfg.xml
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">org.apache.derby.jdbc.ClientDriver</property>
<property name="connection.url">jdbc:derby://localhost:1527/HibernateDb;create=true</property>
<property name="connection.username">admin</property>
<property name="connection.password">admin</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.DerbyDialect</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create-drop</property>
<!-- Names the annotated entity class -->
<mapping class="org.asif.javabrains.dto.UserDetails"/>
</session-factory>
</hibernate-configuration>
Но когда я запускаю Java-программу, которая использует этот класс обслуживания, он, похоже, не удаляет базу данных и не создает ее заново.как говорится в комментарии (я взял файл конфигурации из примеров гибернации).
~~~~ ОБНОВЛЕНИЕ ~~~~
Я пришел к выводу, что hbm2ddl не сбрасывал схему, основываясь на следующемповедение
У меня есть 2 класса, которые выглядят следующим образом
@Entity
public class UserDetails {
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private int userId;
private String userName;
@OneToMany
@JoinTable(name="USER_VEHICLE",
joinColumns=@JoinColumn(name="USER_ID"),
inverseJoinColumns = @JoinColumn(name="VEHICLE_ID")
)
private Collection<Vehicle> vehicles = new ArrayList<Vehicle>() ;
/* getters and setters */
}
и
@Entity
public class Vehicle {
@Id @GeneratedValue
private int vehicleId;
private String vehicleName;
@ManyToOne
@JoinColumn(name="USER_ID")
private UserDetails user;
/* getters and setters */
}
, и соответствующая конфигурация гибернации равна
<!--boiler plate-->
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create</property>
<!-- Names the annotated entity class -->
<mapping class="org.asif.javabrains.dto.UserDetails"/>
<mapping class="org.asif.javabrains.dto.Vehicle"/>
<!--boiler plate-->
Теперь, когда я изменяю вышеупомянутые классы на
@Entity
public class UserDetails {
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private int userId;
private String userName;
@OneToMany(mappedBy="user")
private Collection<Vehicle> vehicles = new ArrayList<Vehicle>() ;
//rest is same
и
@Entity
public class Vehicle {
@Id @GeneratedValue
private int vehicleId;
private String vehicleName;
@ManyToOne
@JoinColumn(name="USER_ID")
private UserDetails user;
//rest is same
Следующее выводится на консоль
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Hibernate: insert into UserDetails (userId, userName) values (default, ?)
Hibernate: values identity_val_local()
Hibernate: insert into Vehicle (vehicleId, USER_ID, vehicleName) values (default, ?, ?)
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not insert: [org.asif.javabrains.dto.Vehicle]
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:92)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.id.insert.AbstractSelectingDelegate.performInsert(AbstractSelectingDelegate.java:64)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2345)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2852)
at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:71)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:320)
at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:203)
at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:129)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)
at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:56)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)
at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:50)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:713)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:701)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:697)
at org.asif.javabrains.hibernate.HibernateTest.main(HibernateTest.java:33)
Caused by: java.sql.SQLSyntaxErrorException: 'USER_ID' is not a column in table or VTI 'ADMIN.VEHICLE'.
at org.apache.derby.client.am.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.client.am.SqlException.getSQLException(Unknown Source)
at org.apache.derby.client.am.Connection.prepareStatement(Unknown Source)
at org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:534)
at org.hibernate.jdbc.AbstractBatcher.prepareStatement(AbstractBatcher.java:116)
at org.hibernate.id.insert.AbstractSelectingDelegate.performInsert(AbstractSelectingDelegate.java:54)
... 16 more
Caused by: org.apache.derby.client.am.SqlException: 'USER_ID' is not a column in table or VTI 'ADMIN.VEHICLE'.
at org.apache.derby.client.am.Statement.completeSqlca(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.parsePrepareError(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.parsePRPSQLSTTreply(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.net.StatementReply.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.net.NetStatement.readPrepareDescribeOutput_(Unknown Source)
at org.apache.derby.client.am.Statement.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.readPrepareDescribeInputOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.flowPrepareDescribeInputOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.prepare(Unknown Source)
at org.apache.derby.client.am.Connection.prepareStatementX(Unknown Source)
... 20 more
Это, кажется, уходит, когда явручную удалите таблицы и выполните снова.Что может быть причиной такого поведения.