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/*.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.flamelephant.fabricmgt.dao.hostmapper" >

  <resultmap type= "com.flamelephant.fabricmgt.entity.po.host" id= "hostmap" >

  <result property= "id" column= "id" jdbctype= "integer" />

  <result property= "hostname" column= "host_name" jdbctype= "varchar" />

  <result property= "ip" column= "ip" jdbctype= "varchar" />

  <result property= "username" column= "user_name" jdbctype= "varchar" />

  <result property= "password" column= "pass_word" jdbctype= "varchar" />

  <result property= "state" column= "state" jdbctype= "other" />

  <result property= "tag" column= "tag" jdbctype= "varchar" />

  <result property= "gmtcreated" column= "gmt_created" jdbctype= "timestamp" />

  <result property= "gmtmodified" column= "gmt_modified" jdbctype= "timestamp" />

  </resultmap>

</mapper>

<select id= "queryall" resultmap= "hostmap" >

     select id,

            host_name,

            ip,

            user_name,

            pass_word,

            state,

            tag,

            gmt_created,

            gmt_modified

     from host

  <where>

     < if test= "id != null and id != ''" >

         and id = #{id}

     </ if >

     < if test= "hostname != null and hostname != ''" >

         and host_name like concat( '%' , #{hostname}, '%' )

     </ if >

     < if test= "ip != null and ip != ''" >

         and ip like concat( '%' , #{ip}, '%' )

     </ if >

     < if test= "username != null and username != ''" >

         and user_name = #{username}

     </ if >

     < if test= "password != null and password != ''" >

         and pass_word = #{password}

     </ if >

     < if test= "state != null and state != ''" >

         and state = #{state}

     </ if >

     < if test= "tag != null and tag != ''" >

         and tag = #{tag}

     </ if >

     < if test= "gmtcreated != null" >

         and gmt_created = #{gmtcreated}

     </ if >

     < if test= "gmtmodified != null" >

         and gmt_modified = #{gmtmodified}

     / if >

  </where>

</select>

/**

  * 条件查询

  *

  * @param host 条件查询

  * @return 对象列表

  */

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 )

/**

  * 批量删除主机

  *

  * @param hostids 主机id数组

  * @return integer

  */ 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>

/**

  * 将多个主机添加至一个主机组

  *

  * @param request

  * @return integer

  */ integer addhostlist(hostandgrouprequest request);