src/main/resources/mapper/TorrentMapper.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.example.myproject.mapper.TorrentMapper">
    <resultMap id="BaseResultMap" type="com.example.myproject.entity.TorrentEntity">
        <id column="info_hash" property="infoHash"/>
        <result column="file_name" property="fileName"/>
        <result column="uploader" property="uploader"/>
        <result column="upload_time" property="uploadTime"/>
        <result column="size" property="size"/>
        <result column="title" property="title"/>
        <result column="description" property="description"/>
        <result column="category" property="category"/>
        <result column="image_url" property="imageUrl"/>
    </resultMap>

    <select id="selectByInfoHash" resultMap="BaseResultMap">
        SELECT * FROM torrent WHERE info_hash = #{infoHash}
    </select>
    <select id="selectBySeedId" resultMap="BaseResultMap">
        SELECT * FROM torrent WHERE seed_id = #{seedId}
    </select>




    <update id="update" parameterType="com.example.myproject.entity.TorrentEntity">
        UPDATE torrent
        SET file_name = #{fileName},
        uploader = #{uploader},
        upload_time = #{uploadTime},
        size = #{size},
        title = #{title},
        description = #{description},
        category = #{category},
        image_url = #{imageUrl}
        WHERE info_hash = #{infoHash}
    </update>
    <select id="search" resultType="com.example.myproject.entity.TorrentEntity">
        SELECT * FROM torrent
        <where>
            <if test="param.category != null">
                AND category = #{param.category}
            </if>

            <!--        <if test="param.free != null and param.free != ''">-->
            <!--            AND free = #{param.free}-->
            <!--        </if>-->
            <if test="param.free != null">
            <choose>
                <!-- 筛选“正在促销中”的种子 -->
                <when test="param.free == true">
                    AND EXISTS (
                    SELECT 1 FROM promotion p
                    WHERE
                    JSON_CONTAINS(p.applicable_torrent_ids, JSON_ARRAY(t.id))
                    AND NOW() BETWEEN p.start_time AND p.end_time
                    AND p.is_deleted = 0
                    )
                </when>
                <!-- 筛选“未在促销中”的种子 -->
                <otherwise>
                    AND NOT EXISTS (
                    SELECT 1 FROM promotion p
                    WHERE
                    JSON_CONTAINS(p.applicable_torrent_ids, JSON_ARRAY(t.id))
                    AND NOW() BETWEEN p.start_time AND p.end_time
                    AND p.is_deleted = 0
                    )
                </otherwise>
            </choose>
            </if>

            <if test="param.likeExpressions != null and param.likeExpressions.size > 0">
                AND (
                <foreach collection="param.likeExpressions" item="item" open="(" separator=" AND " close=")">

                    ( title LIKE CONCAT('%', #{item}, '%') ) or ( description LIKE CONCAT('%', #{item}, '%') ) or ( tags LIKE CONCAT('%', #{item}, '%') )
                </foreach>
                )
            </if>
        </where>

        <if test="param.prop != null and param.sort != null">
            ORDER BY ${param.prop} ${param.sort}
        </if>
    </select>
    <select id="checkFavorite" resultType="boolean">
        SELECT COUNT(*) > 0
        FROM favorite
        WHERE seed_id = #{seedId} AND user_id = #{userId}
    </select>
    <insert id="addFavorite">
        INSERT INTO favorite (seed_id, user_id)
        VALUES (#{seedId}, #{userId})
    </insert>
    <delete id="removeFavorite">
        DELETE FROM favorite
        WHERE seed_id = #{seedId} AND user_id = #{userId}
    </delete>
    <select id="selectMyFavorite" resultType="com.example.myproject.entity.TorrentEntity">
        SELECT t.*
        FROM torrent t
        JOIN favorite f ON t.id = f.seed_id
        WHERE f.user_id = #{userId}
    </select>
    <update id="incrementViews" parameterType="long">
        UPDATE torrent
        SET views = views + 1
        WHERE id = #{id}
    </update>
    <select id="selectColdTorrents" resultType="com.example.myproject.entity.TorrentEntity">
        SELECT * FROM torrent
        WHERE views &lt; #{threshold}
        ORDER BY views ASC
    </select>



</mapper>