water-monitor-api/ruoyi-code/src/main/resources/mapper/camera/CameraMapper.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.ruoyi.code.camera.mapper.CameraMapper">

    <select id="queryCameraList" resultType="com.ruoyi.code.camera.domain.Camera">
        select * from camera where devsn not in (
            select camera_sn from sc_station_info
        )
    </select>

    <select id="queryCameraBYSid" resultType="com.ruoyi.code.camera.domain.Camera">
        select
            c.*
        from
            camera c,
            sc_station_info s
        where
            c.devsn = s.camera_sn
          and s.id = #{sid}
    </select>

    <select id="queryPage" resultType="com.ruoyi.code.camera.domain.Camera">
        select * from camera

        <where>
            <if test="params.devsn!= null and params.devsn != ''">
                and devsn like concat('%',#{params.devsn},'%')
            </if>
            <if test="params.name != null and params.name != ''">
                and name like concat('%',#{params.name},'%')
            </if>
        </where>
    </select>
</mapper>