Mybatis 一对多关联查询collection用法

使用resultMap, select 标签, resultMap的中的collection表示一对多,column对应select标签中的sql里的字段或者别名,当两个表字段名称有相同的情况下,可以定义别名。

<resultMap id="authorWorksInfo" type="package.vo.AuthorWorksInfo">

    <id column="id" property="id"/>

    <result column="name" property="name"/>

    <result column="gender" property="gender"/>

    <collection property="books" ofType="package.vo.Book">

        <id column="bid" property="bid"/>

        <result column="aid" property="aid"/>

        <result column="bookName" property="bookName"/>

    </collection>

</resultMap>

<select id="queryAuthorWorks" resultMap="authorWorksInfo">

    select a.id, a.name, a.gender,

        b.id as bid, b.author_id as aid, b.name as bookName

    from author a 

    left join book b

    on a.id = b.aid

</select>

上面sql对应的要返回的AuthorWorksInfo类的属性如下:

private Long id;

private String name;

private String gender;

private List<Book> books;

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转载自blog.csdn.net/suoyx/article/details/109061102
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