单一主键
一、assigned 由java应用程序负责生成(手工赋值)
二、native 由底层数据库自动生成标识符,如果是Mysql就是increment,如果是Oracle就是sequence。
在实体类映射的主键id标签里面的generator标签改。
![](https://img.haomeiwen.com/i5384883/b6fb1c5e856b2735.png)
例1:
![](https://img.haomeiwen.com/i5384883/fd07d44f255c14cc.png)
例2:
![](https://img.haomeiwen.com/i5384883/f5c5f015985f0189.png)
基本类型
![](https://img.haomeiwen.com/i5384883/c2425c4fc20182dd.png)
注意画红色圈圈的——易错
![](https://img.haomeiwen.com/i5384883/7a5c2e4b7af2d87e.png)
![](https://img.haomeiwen.com/i5384883/edc7eaa8c7f71b1d.png)
对象类型
![](https://img.haomeiwen.com/i5384883/523b1f59cc1476a9.png)
![](https://img.haomeiwen.com/i5384883/a99228008f3af2a2.png)
添加一个照片字段,并重新生成学生关系映射
![](https://img.haomeiwen.com/i5384883/93b70e48be5ca5ae.png)
![](https://img.haomeiwen.com/i5384883/0a35ac9d96d65576.png)
![](https://img.haomeiwen.com/i5384883/1c934480bc37dd09.png)
组件属性
![](https://img.haomeiwen.com/i5384883/0b01d9fb14e81386.png)
如:当Student类里的address属性是另外一个类的时候,就会出现如上图这样的信息。
![](https://img.haomeiwen.com/i5384883/418380cf485b29f6.png)
单表操作CRUD实例
其他的增删改查看 “Hibernate—— 创建与配置” 里面的
![](https://img.haomeiwen.com/i5384883/cccdc421a8ade1ee.png)
![](https://img.haomeiwen.com/i5384883/6e42b64797c35b2d.png)
![](https://img.haomeiwen.com/i5384883/ec83cb94066935fb.png)
![](https://img.haomeiwen.com/i5384883/57de2a4f3882befc.png)
System.out.println(s.getClass().getName()); //就能看出返回的是什么对象
![](https://img.haomeiwen.com/i5384883/591de49028c905cc.png)
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