MyBatis 一对一查询方式一

一、创建数据库 SQL

CREATE TABLE husband (husbandId INT, husbandName VARCHAR(20), husbandAge INT);
CREATE TABLE wife (wifeId INT, hId INT, wifeName VARCHAR(20), wifeAge INT);

二、创建与数据库表对应的实体类

public class Husband implements Serializable {

    private int husbandId;
    private String husbandName;
    private int husbandAge;
    ...
}
public class Wife implements Serializable {

    private int wifeId;
    private int hid;
    private String wifeName;
    private int wifeAge;
    ...
}

二、创建与查询结果对应的实体类

public class HusbandWife implements Serializable {

    private String husbandName;
    private int husbandAge;
    private String wifeName;
    private int wifeAge;
	...
}

注意:与查询结果对应的实体类也可以通过继承 Wife 或 Husband 类实现。

三、持久层接口

public interface IHusbandWifeDao {

    List<HusbandWife> findAll();
}

四、持久层接口映射文件

<mapper namespace="chu.yi.bo.dao.IHusbandWifeDao">
	<select id="findAll" resultType="chu.yi.bo.domain.HusbandWife">
	    select h.husbandName,h.husbandAge,w.wifeName,w.wifeAge from husband h,wife w where h.husbandId = w.hid;
	</select>
</mapper>

五、测试

List<HusbandWife> husbandWifeList = husbandWifeDao.findAll();
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