Java 使用getGeneratedKeys-MyBatis时获取更新记录主键失败

我正试图在MyBatis（v3.5.1）中以这种方式获取更新记录主键：

现在我获取更新记录id失败，该id是我的主键。这是我的调试输出：

---

我应该如何获得更新记录的id？

我是这样实现的：

int updateForFreeSeat(RoomSeat roomSeat);

    <select id="updateForFreeSeat"
            parameterType="com.sportswin.soa.room.model.entity.RoomSeat" resultType="com.sportswin.soa.room.model.entity.RoomSeat">
        set @update_id := 0;
        UPDATE r_room_seat SET status = #{record.status,jdbcType=INTEGER},
        id = (SELECT @update_id := id),
        user_id = #{record.userId,jdbcType=BIGINT},
        robot_flag = #{record.robotFlag,jdbcType=TINYINT}
        WHERE room_play_id = #{record.roomPlayId,jdbcType=BIGINT} and status = 0
        LIMIT 1;
        select <include refid="Base_Column_List" /> from r_room_seat where id = @update_id;
    </select>

我受到这个问题的启发

    <select id="updateForFreeSeat"
            parameterType="com.sportswin.soa.room.model.entity.RoomSeat" resultType="com.sportswin.soa.room.model.entity.RoomSeat">
        set @update_id := 0;
        UPDATE r_room_seat SET status = #{record.status,jdbcType=INTEGER},
        id = (SELECT @update_id := id),
        user_id = #{record.userId,jdbcType=BIGINT},
        robot_flag = #{record.robotFlag,jdbcType=TINYINT}
        WHERE room_play_id = #{record.roomPlayId,jdbcType=BIGINT} and status = 0
        LIMIT 1;
        select <include refid="Base_Column_List" /> from r_room_seat where id = @update_id;
    </select>

RoomSeat updateForFreeSeat(@Param(value = "record")RoomSeat roomSeat);