Hibernate为Oracle自动创建表且主键自增

转自http://hua04104.javaeye.com/blog/669104

1.注意：实体类映射表字段时不要使用oralce关键字，否则不能映射成功。
2.步骤：
    （1）往oralce里建一个sequence:     

     Sql代码 

     create sequence seq_id_supervision minvalue 1 start with 1 increment by 1 

                  create sequence seq_id_supervision
                      minvalue 1
                      start with 1
                      increment by 1
         

         注：如果多个表要映射自增长主键，每个表要建一个sequence。
    （2）model映射配置：
        

< id   name = "id" >
       < generator   class = "sequence" >
            < param   name = "sequence" >
               seq_id_letter
            </ param >
       </ generator >
</ id >

          <id name="id">
	        <generator class="sequence">
		       <param name="sequence">
			     seq_id_letter
			</param>
		</generator>
	 </id>
         

    （3）Hibernate映射文件配置：
        

< hibernate-configuration >
    < session-factory >
        < property   name = "hibernate.connection.driver_class" >
              oracle.jdbc.driver.OracleDriver
        </ property >
        < property   name = "hibernate.connection.url" >
              jdbc:oracle:thin:@localhost:1521:jf
        </ property >
        < property   name = "hibernate.connection.username" > jf </ property >
        < property   name = "hibernate.connection.password" > jf </ property >
        < property   name = "hibernate.dialect" >
             org.hibernate.dialect.OracleDialect
        </ property >
        < property   name = "hibernate.show_sql" > true </ property >
        < property   name = "hibernate.hbm2ddl.auto" > update </ property >
        < property   name = "hibernate.cache.provider_class" >
              org.hibernate.cache.HashtableCacheProvider
        </ property >
        < mapping   resource = "com/chinasoft/jfb/model/LetterInformation.hbm.xml"   />
     </ session-factory >
</ hibernate-configuration >

         <hibernate-configuration>
<session-factory>
	<property name="hibernate.connection.driver_class">
		oracle.jdbc.driver.OracleDriver
	</property>
	<property name="hibernate.connection.url">
		jdbc:oracle:thin:@localhost:1521:jf
	</property>
	<property name="hibernate.connection.username">jf</property>
	<property name="hibernate.connection.password">jf</property>
	<property name="hibernate.dialect">
             org.hibernate.dialect.OracleDialect
        </property>
	<property name="hibernate.show_sql">true</property>
	<property name="hibernate.hbm2ddl.auto">update</property>
	<property name="hibernate.cache.provider_class">
		org.hibernate.cache.HashtableCacheProvider
	</property>
	<mapping resource="com/chinasoft/jfb/model/LetterInformation.hbm.xml" />
</session-factory>
</hibernate-configuration>