我想使用 Hibernate 和 MySql 创建 embedded 对象列表。
但我咳出了一堆错误:
Hibernate: alter table USERS drop foreign key FK_qymdwjo8d0eu0lhfd3ngfs74d
2014-07-09 15:40:47 ERROR SchemaExport:425 - HHH000389: Unsuccessful: alter table USERS drop foreign key FK_qymdwjo8d0eu0lhfd3ngfs74d
2014-07-09 15:40:47 ERROR SchemaExport:426 - Can't DROP 'FK_qymdwjo8d0eu0lhfd3ngfs74d'; check that column/key exists
Hibernate: drop table if exists USERS
2014-07-09 15:40:48 ERROR SchemaExport:425 - HHH000389: Unsuccessful: drop table if exists USERS
2014-07-09 15:40:48 ERROR SchemaExport:426 - Cannot delete or update a parent row: a foreign key constraint fails
Hibernate: drop table if exists hibernate_unique_key
Hibernate: create table USERS (id integer not null, city varchar(35), pincode varchar(35), state varchar(35), street varchar(35), description varchar(35), joinedDate date, name varchar(35), ADDRESSES_ID bigint not null, primary key (ADDRESSES_ID))
2014-07-09 15:40:48 ERROR SchemaExport:425 - HHH000389: Unsuccessful: create table USERS (id integer not null, city varchar(35), pincode varchar(35), state varchar(35), street varchar(35), description varchar(35), joinedDate date, name varchar(35), ADDRESSES_ID bigint not null, primary key (ADDRESSES_ID))
2014-07-09 15:40:48 ERROR SchemaExport:426 - Table 'users' already exists
Hibernate: alter table USERS add constraint FK_qymdwjo8d0eu0lhfd3ngfs74d foreign key (id) references USERS (ADDRESSES_ID)
2014-07-09 15:40:48 ERROR SchemaExport:425 - HHH000389: Unsuccessful: alter table USERS add constraint FK_qymdwjo8d0eu0lhfd3ngfs74d foreign key (id) references USERS (ADDRESSES_ID)
2014-07-09 15:40:48 ERROR SchemaExport:426 - Cannot add foreign key constraint
Hibernate: create table hibernate_unique_key ( next_hi integer )
Hibernate: insert into hibernate_unique_key values ( 0 )
2014-07-09 15:40:48 INFO SchemaExport:405 - HHH000230: Schema export complete
Hibernate: insert into USERS (city, pincode, state, street, description, joinedDate, name) values (?, ?, ?, ?, ?, ?, ?)
Hibernate: select next_hi from hibernate_unique_key for update
Hibernate: update hibernate_unique_key set next_hi = ? where next_hi = ?
Hibernate: insert into USERS (id, ADDRESSES_ID, city, pincode, state, street) values (?, ?, ?, ?, ?, ?)
2014-07-09 15:40:48 WARN SqlExceptionHelper:144 - SQL Error: 1054, SQLState: 42S22
2014-07-09 15:40:48 ERROR SqlExceptionHelper:146 - Unknown column 'ADDRESSES_ID' in 'field list'
2014-07-09 15:40:48 INFO AbstractBatchImpl:208 - HHH000010: On release of batch it still contained JDBC statements
org.hibernate.exception.SQLGrammarException: could not execute statement
at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:80)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:126)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:112)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:190)
at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:62)
at org.hibernate.persister.collection.AbstractCollectionPersister.recreate(AbstractCollectionPersister.java:1311)
at org.hibernate.action.internal.CollectionRecreateAction.execute(CollectionRecreateAction.java:67)
at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:463)
at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:349)
at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:350)
at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:56)
at org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1222)
at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:425)
at org.hibernate.engine.transaction.internal.jdbc.JdbcTransaction.beforeTransactionCommit(JdbcTransaction.java:101)
at org.hibernate.engine.transaction.spi.AbstractTransactionImpl.commit(AbstractTransactionImpl.java:177)
at com.demo.hibernate.HibernateDemo.createUser(HibernateDemo.java:59)
at com.demo.hibernate.HibernateDemo.main(HibernateDemo.java:37)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'ADDRESSES_ID' in 'field list'
这是 main() :
public static void main(String[] args) {
try {
HibernateDemo demo = new HibernateDemo();
UserDetails user = new UserDetails();
Address address = new Address();
address.setStreet("Name");
address.setCity("Kiev");
address.setPincode("00000");
address.setState("My state");
Address addr = new Address();
addr.setStreet("new name");
addr.setCity("Lviv");
addr.setPincode("79040");
addr.setState("state");
user.getListOfAddresses().add(address);
user.getListOfAddresses().add(addr);
user.setUserName("Carl");
user.setJoinedDate(new Date());
user.setDescription("it is cool guy");
user.setAddress(address);
demo.createUser(user);
demo.listUsers();
user.setUserName("Bruno Shults");
demo.updateUser(user);
demo.listUsers();
} catch (Exception e) {
e.printStackTrace();
} finally {
System.runFinalizersOnExit(true);
System.exit(1);
}
用户详细信息 类:
@Entity
@Table(name = "USERS")
public class UserDetails {
@Id
@GeneratedValue
@Column(name = "id")
private int userId;
@Column(name = "name", length = 35)
private String userName;
@Temporal(TemporalType.DATE)
private Date joinedDate;
@Column(length = 35)
private Address address;
@Column(length = 35)
private String description;
@ElementCollection
@JoinTable(name = "USERS", joinColumns = @JoinColumn(name = "id"))
@GenericGenerator(name = "hilo-gen", strategy = "hilo")
@CollectionId(columns = {@Column(name = "ADDRESSES_ID")}, generator = "hilo-gen", type = @Type(type = "long"))
private Collection<Address> listOfAddresses = new ArrayList<Address>();
// getters and setters
地址 类:
@Embeddable
public class Address {
@Column(length = 35)
private String street;
@Column(length = 35)
private String city;
@Column(length = 35)
private String state;
@Column(length = 35)
private String pincode;
// getters and setters
cfg xml 文件:
<hibernate-configuration>
<session-factory>
<!--Database connection settings-->
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/hibernatedb</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">secret</property>
<!--JDBC connection pool-->
<property name="hibernate.connection.pool_size">2</property>
<!--SQL dialect-->
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<!--Disable the second level cache-->
<property name="cache.provider_class">org.hibernate.cache.internal.NoCachingRegionFactory</property>
<!--Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!--Drop and recreate the database schema on startup-->
<property name="hbm2ddl.auto">create</property>
<!--<property name="hbm2ddl.auto">update</property>-->
<!-- List of XML mapping files -->
<mapping class="com.demo.dto.UserDetails"/>
这是 DB 击打的样子:
和图:
我不明白为什么它会创建
hibernate_unique_key 表？它不应该。有什么建议吗？
最佳答案
那么这些线
Hibernate: create table hibernate_unique_key ( next_hi integer )
Hibernate: insert into hibernate_unique_key values ( 0 )
出现是因为
@GenericGenerator(name = "hilo-gen", strategy = "hilo")
在你的地址
hilo:生成整数、长型或短型 ID。这使用高-低算法。顾名思义，它取决于最高的表 ID，然后读取可能的最低可用值。
阅读更多相关信息 here
关于java - 使用 Hibernate 的 ERROR SchemaExport，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/24654231/