Question

ibatis2.3中，怎样实现多张表联合查询

Answer 1

我这里用的是mybaits的，两表查询在xml配置
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<resultMap type="com.szy.bean.User" id="user_book" >
<id property="id" column="id"/>
<result property="userName" column="username"/>
<result property="userAddress" column="useraddress"/>
<association property="book" column="book_id" resultMap="book"></association>
</resultMap>

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在上面用association 关联了book的resultMap

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<!-- book -->
<resultMap type="com.szy.bean.Book" id="book">
<result property="bookName" column="book_name"/>
</resultMap>

<!-- 多表查询 -->
<select id="selectUserAndBooks" resultMap="user_book" >
select u.id,u.username ,u.useraddress,b.book_name from user u right outer join book b on u.id= b.book_id
</select>
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实体bean为

public class User {
private int id;
private String userName;
private String userAge;
private String userAddress;
private Book book;

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我不知道ibatis怎么弄的，没实践过，但mybatis这样写是可以联表查的