PaperExercisesMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.meishu.mapper.PaperExercisesMapper">

    <select id="getPaperExercises" parameterType="long" resultType="com.meishu.vo.exercise.LabelExercisesVO">
        SELECT
            t2.*,
            t3.label,
            t.id as paperExerciseId
        FROM
            paper_exercises t
            LEFT JOIN exercise_dict t2 ON t.exercise_id = t2.id
            LEFT JOIN label_dict t3 ON t2.label_id = t3.id
            where t.delete_date is null
            and t2.delete_date is null
            and t3.delete_date is null
            and t.paper_id = #{paperId}
    </select>

</mapper>