在休眠中使用身份插入数据时出错

Question

我遇到了在 STOCK_ID 是标识且 STOCK_NAME 是字符串的数据库中插入数据的问题。在数据库中插入数据时，它显示了一个下面提到的异常。请指导我纠正问题。

Hibernate: insert into mkyongdb.system.STOCK (STOCK_NAME) values (?)
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not insert: [com.mkyong.user.Stock]
    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 com.mkyong.common.App.main(App.java:45)
Caused by: java.sql.SQLSyntaxErrorException: ORA-00926: missing VALUES keyword

    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:440)
    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:396)
    at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:837)
    at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:445)
    at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:191)
    at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:523)
    at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:207)
    at oracle.jdbc.driver.T4CPreparedStatement.executeForRows(T4CPreparedStatement.java:1010)
    at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1315)
    at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3576)
    at oracle.jdbc.driver.OraclePreparedStatement.executeUpdate(OraclePreparedStatement.java:3657)
    at oracle.jdbc.driver.OraclePreparedStatementWrapper.executeUpdate(OraclePreparedStatementWrapper.java:1350)
    at org.hibernate.id.insert.AbstractSelectingDelegate.performInsert(AbstractSelectingDelegate.java:57)
    ... 16 more

Stock.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.mkyong.user.Stock" table="STOCK" catalog="mkyongdb">
        <id name="stockId" type="java.lang.Integer">
            <column name="STOCK_ID" />
            <generator class="identity" />
        </id>
        <property name="stockName" type="string">
            <column name="STOCK_NAME" length="10"  />
        </property>

        <!-- <one-to-one name="stockDetail" class="com.mkyong.user.StockDetail"
            cascade="save-update"></one-to-one> -->
    </class>
</hibernate-mapping>

hibernate.cfg.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <property name="hibernate.connection.url">jdbc:oracle:thin:@127.0.0.1:1521/xe</property>
        <property name="hibernate.connection.username">system</property>
        <property name="hibernate.connection.password">admin</property>
        <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>

        <property name="show_sql">true</property>
        <property name="hibernate.default_schema">system</property> 
        <property name="hibernate.hbm2ddl.auto">validate</property>
        <mapping resource="com/mkyong/user/DBUser.hbm.xml"></mapping>
        <mapping resource="com/mkyong/user/Stock.hbm.xml" />
    <mapping resource="com/mkyong/user/StockDetails.hbm.xml" />
    </session-factory>
</hibernate-configuration>

Stock.java

package com.mkyong.user;

public class Stock implements java.io.Serializable {

    private Integer stockId;
    private String stockName;
    //private StockDetail stockDetail;

    /*public StockDetail getStockDetail() {
        return stockDetail;
    }
    public void setStockDetail(StockDetail stockDetail) {
        this.stockDetail = stockDetail;
    }*/

    public Stock() {
        //super();
        // TODO Auto-generated constructor stub
    }
    public Stock(Integer stockId, String stockName) {
        super();
        this.stockId = stockId;
        this.stockName = stockName;
    }
    public Integer getStockId() {
        return stockId;
    }

    public void setStockId(Integer stockId) {
        this.stockId = stockId;
    }
    public String getStockName() {
        return stockName;
    }
    public void setStockName(String stockName) {
        this.stockName = stockName;
    }






}

Main.java

Session session = HibernateUtil.getSessionFactory().openSession();

        session.beginTransaction();

        Stock stock = new Stock();

        stock.setStockName("sam");


        session.save(stock);
        session.getTransaction().commit();

创建查询：

CREATE TABLE STOCK
(
  STOCK_ID numeric(10) not null,
  STOCK_NAME varchar2(50) not null,
  CONSTRAINT STOCK_PK PRIMARY KEY (STOCK_ID)
);

Answer 1

• 我认为mkyongdb 是您的架构，其中包含名为STOCK 的表。所以， 在 insert 声明。

• STOCK_ID 是必填字段，在insert 语句中缺失。

  (顺便说一句，如果你使用Oracle12c，这个字段可能不会包含在insert语句中，只要在create table DDL语句中直接定义为STOCK_ID numeric(10) GENERATED by default on null as IDENTITY，不需要任何其他机制，如触发器。如果您有 12c 之前的版本，则可以创建一个 before insert trigger，其中包含 :new.STOCK_ID := seq_stock_id.nextval; 语句，其中 seq_stock_id 是一个序列）