mybatis 查询集合里每一条数据包含子查询结果集。一对多查询，一对一查询，子查询。 / 四六文摘

实现方案：子查询

我重新写了一个实体类来作为返回给前端

public class LanguageVO {
   private String code;
   private String zhLanguage; //中文
   private String cnLanguage; //英文
   private List<TLanguageIta> list; //其它语言

get set方法略.....

}

原实体类：

public class LanguageI {
private String id;

private String code;

private String languageType;

private String content;

get set方法略..

}

方案一：直接在类中用注解方式实现：

@Select("select code from language group by code")
@Results({
@Result(property = "code", column = "code"),
@Result(property = "list", column = "code",
many =@Many(select ="com.mapper.TLanguageItaMapper.getLanguageListByCode")),
@Result(property = "zhLanguage", column = "code",
one =@One(select ="com.mapper.TLanguageItaMapper.getZhLanguage")),
@Result(property = "cnLanguage", column = "code",
one =@One(select ="com.mapper.TLanguageItaMapper.getCnLanguage"))
})
List<LanguageVO> getLanguageListByPage();

@Select("select t.id,t.code,t.language_type as languageType,"
+ "t.content,t.remark from language t where t.code = #{code}")
List<TLanguageIta> getLanguageListByCode(@Param("code")String code);
@Select("select t.content from language t where t.code = #{code} and t.language_type = '1'")
String getZhLanguage(@Param("code")String code);
@Select("select t.content from language t where t.code = #{code} and t.language_type = '2'")
String getCnLanguage(@Param("code")String code);

方案二：在xml中实现

<select id="getZhLanguage" resultType="String">
   select t.content from language t where t.code = #{code} and t.language_type = '1'
</select>
<select id="getCnLanguage" resultType="String">
   select t.content from language t where t.code = #{code} and t.language_type = '2'
</select>
<select id="getLanguageListByCode" resultMap="BaseResultMap">
   select t.id,t.code,t.language_type,t.content,t.remark from language t
   where t.code = #{code}
</select>

mybatis 查询集合里每一条数据包含子查询结果集。一对多查询，一对一查询，子查询。

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