java hibernate'字段列表'中的未知列''

Question

我需要帮助。

当我使用getAllStreets()方法时，我在HQL中有错误：

org.hibernate.exception.SQLGrammarException: Unknown column 'this_1_.houses_id' in 'field list'

我猜他一定要写this_1_id代替this_1_.houses_id

可能是我做错了实体和关系吗？

2个实体-房屋和街道

ER-model：

Table Streets

• ID
• Name
• Houses_id

Table Houses

• ID
• name

My Classes:

Street

@Entity
@Table(name="Streets")
public class Street {
    private Long id;
    private String name;
    private Long houses_id;
    private House house;
    public Street(){}    
    @Id
    @GeneratedValue(generator="increment")
    @GenericGenerator(name="increment", strategy="increment")
    @Column(name="id")
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    @Column(name="name")
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    @ManyToOne
    @JoinTable(name="Houses", joinColumns = @JoinColumn(name="id"), inverseJoinColumns=@JoinColumn(name="houses_id"))
    public House getHouse() {
        return house;
    }
    public void setHouse(House house) {
        this.house = house;
    }
    @Column(name="houses_id")
    public Long getHouses_id() {
        return houses_id;
    }
    public void setHouses_id(Long houses_id) {
        this.houses_id = houses_id;
    }
}

House

@Entity
@Table(name="Houses")
public class House {

    private Long id;
    private String name;
    public House(){}

    @Id
    @GeneratedValue(generator = "increment")
    @GenericGenerator(name="increment", strategy="increment")
    @Column(name="id")
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    @Column(name="name")
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

My DAOIMP：

StreetDAOImp：

public class StreetDAOImpl implements StreetDAO {
    @Override
    public void addStreet(Street street) throws SQLException {
        // TODO Auto-generated method stub
        Session session = null;
        try {
            session = HibernateUtil.getSessionFactory().openSession();
            session.beginTransaction();

            session.save(street);
            session.getTransaction().commit();
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        finally{
            if(session != null && session.isOpen()){
                session.close();
            }
        }
    }
    @Override
    public Collection getAllStreets() throws SQLException {
        // TODO Auto-generated method stub
        Session session = null;
        List<Street> streets = new ArrayList<Street>(); 
        try {
            session = HibernateUtil.getSessionFactory().openSession();

            streets = session.createCriteria(Street.class).list();
            //Query q = session.createQuery("select str from com.ff.model.Street str join str.houses h where h.id = str.houses_id");
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        return streets;
    }
}

HouseDAOImpl：

public class HouseDAOImpl implements HouseDAO {

    @Override
    public void addHouse(House house)throws SQLException {
        // TODO Auto-generated method stub
        Session session = null;
        try {
            session = HibernateUtil.getSessionFactory().openSession();
            session.beginTransaction();
            session.save(house);
            session.getTransaction().commit();
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        finally{
            if(session != null && session.isOpen()){
                session.close();
            }
        }
    }

    @Override
    public Collection getAllHouses() throws SQLException {
        // TODO Auto-generated method stub
        Session session = null;
        List<House> houses = new ArrayList<House>();

        try {
            session = HibernateUtil.getSessionFactory().openSession();
            houses = session.createCriteria(House.class).list();
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
         finally {
              if (session != null && session.isOpen()) {
                session.close();
              }

    }
    return houses;
}}

错误：

log4j:WARN No appenders could be found for logger (org.jboss.logging). log4j:WARN Please initialize the log4j system properly. Hibernate: select this_.id as id1_1_, this_.houses_id as houses2_1_1_, this_.name as name1_1_, this_1_.houses_id as houses3_0_1_, house2_.id as id0_0_, house2_.name as name0_0_ from Streets this_ left outer join Houses this_1_ on this_.id=this_1_.id left outer join Houses house2_ on this_1_.houses_id=house2_.id org.hibernate.exception.SQLGrammarException: Unknown column 'this_1_.houses_id' in 'field list' at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:82) at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49) at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125) at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:110) at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:129) at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:81) at $Proxy14.executeQuery(Unknown Source) at org.hibernate.loader.Loader.getResultSet(Loader.java:2031) at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1832) at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1811) at org.hibernate.loader.Loader.doQuery(Loader.java:899) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:341) at org.hibernate.loader.Loader.doList(Loader.java:2516) at org.hibernate.loader.Loader.doList(Loader.java:2502) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2332) at org.hibernate.loader.Loader.list(Loader.java:2327) at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:124) at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1621) at org.hibernate.internal.CriteriaImpl.list(CriteriaImpl.java:374) at com.ff.DAO.StreetDAOImpl.getAllStreets(StreetDAOImpl.java:48) at FFMain.main(FFMain.java:58) Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'this_1_.houses_id' in 'field list' at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.Util.getInstance(Util.java:381) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1030) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3491) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3423) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1936) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2060) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2542) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1734) at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1885) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:122) ... 16 more

Answer 1

查看以下代码：

@JoinTable(name="Houses", joinColumns = @JoinColumn(name="id"), inverseJoinColumns=@JoinColumn(name="houses_id"))

我不确定您要在这里实现什么，但是JoinTable通常用于解决与中间表的ManyToMany关系。因此，此代码暗示您具有Houses带有id和houses_id列的表。错误消息说，没有houses_id在Houses表中（这听起来合乎逻辑的我）
也许你应该尝试多对一和JoinColumn呢？例如：

@JoinColumn(name="house_id")

或者houses_id这是您在Streets表中的外键。如果这确实是多对一关系，那么听起来很奇怪。