mybatis框架的xml映射文件常用查询指南

<dependency>
 <groupId>org.mybatis.spring.boot</groupId>
 <artifactId>mybatis-spring-boot-starter</artifactId>
 <version>2.1.3</version>
</dependency>

mybatis:
  mapper-locations: classpath:mapper
List<Host> queryAll(Host host);

<!--通过主键批量删除-->
<delete id="deleteHostByIds" parameterType="java.lang.Integer">
 delete
    from host
            where id in
    <if test="hostIds != null and hostIds.length > 0">
        <foreach item="id" collection="hostIds" index="index" open="(" separator="," close=")">
            #{id}
        </foreach>
    </if>
 </delete>

delete from host where id in(1,2,3)

Integer deleteHostByIds(@Param("hostIds") Long[] hostIds);

<!--批量增加-->
<insert id="addHostList">
 insert into host_and_group(host_group_id, host_id)
       values
    <foreach collection="hostGroupIdList" item="hostGroupId" index="index" separator=",">
            (#{hostGroupId}, #{hostId})
    </foreach>
</insert>

Integer addHostList(HostAndGroupRequest request);