mybatis基本使用-优快云博客

本文链接：https://blog.youkuaiyun.com/daniuniuniu/article/details/136539887

本文围绕MyBatis展开，介绍了其环境搭建，包括引入依赖、配置扫描和数据库连接等。阐述了XML映射文件的传参方式、结果映射及高级结果映射。讲解了动态SQL的多种标签使用，如if、choose、trim、foreach等。还提及了MyBatis的一级缓存默认开启，二级缓存非特殊情况不开启。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

一、mybatis的环境搭建

引入依赖

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.3.12.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.3</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.21</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-maven-plugin</artifactId>
            <version>1.4.0</version>
        </dependency>
    </dependencies>

配置mapper接口扫描

@SpringBootApplication
@MapperScan("com.haierac.mybatis.example.mapper")
public class MainApplication {
    public static void main(String[] args) {
        SpringApplication.run(MainApplication.class, args);
    }
}

配置数据库连接和Mapper.xml文件位置

spring.application.name=mybatis-example
server.port=8889

spring.datasource.url=jdbc:mysql://192.168.100.171:3306/vrv_cloudplatform_project_center?useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

#classpath*:mapper/**/*Mapper.xml
mybatis.mapper-locations=classpath*:mapper/*Mapper.xml
#开启是否打印sql
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
#别名包
mybatis.type-aliases-package=com.haierac.mybatis.example.pojo
#开启驼峰命名识别
mybatis.configuration.map-underscore-to-camel-case=true

classpath 和 classpath* 的区别主要在于如何搜索和加载资源。当使用 classpath 前缀时，Spring 将从类路径中搜索资源，并在找到第一个匹配的资源后立即停止搜索。而当使用 classpath* 前缀时，Spring 将从所有类路径中搜索资源，包括 JAR 文件中的类路径。

mybatis代码自动生成插件

<build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.4.0</version>
                <configuration>
                    <verbose>true</verbose>
                    <overwrite>true</overwrite>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <version>8.0.21</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>

代码自动生成配置文件

<!DOCTYPE generatorConfiguration PUBLIC
        "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
    <!-- MyBatis3Simple风格 -->
    <context id="simple" targetRuntime="MyBatis3Simple">

        <property name="javaFileEncoding" value="UTF-8"/>
        <!--生成mapper.xml时覆盖原文件-->
        <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin"/>

        <commentGenerator>
            <!-- 是否去除自动生成的注释 true：是 ： false:否。 自动生成注释太啰嗦，可以编码扩展CommentGenerator -->
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>

        <!-- 数据库连接 -->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://192.168.100.171:3306/vrv_cloudplatform_project_center?useUnicode=true&amp;characterEncoding=utf8&amp;tinyInt1isBit=true&amp;serverTimezone=UTC"
                        userId="root" password="123456">
            <!-- 设置为true就只读取cloudplatform_access_control_center下的表, 否则会优先读取到mysql的user表  -->
            <property name="nullCatalogMeansCurrent" value="true"/>
        </jdbcConnection>

        <!-- 生成PO的包名和位置 -->
        <javaModelGenerator targetPackage="com.haierac.mybatis.example.entity" targetProject="src/main/java"/>

        <!-- 生成XML映射文件的包名和位置 -->
        <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/>

        <!-- 生成Mapper接口的包名和位置 -->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.haierac.mybatis.example.mapper" targetProject="src/main/java"/>

        <!-- 要生成对应表配置 -->
        <table tableName="vrv_area" domainObjectName="Area" >
            <!-- 自增主键列 -->
            <generatedKey column="id" sqlStatement="MYSQL" identity="true"/>
            <!-- tinyint映射为Integer -->
            <!--<columnOverride column="role" javaType="Integer" jdbcType="TINYINT"/>-->
        </table>
    </context>
</generatorConfiguration>

二、XML映射文件

1、传参方式

 <select
  id="selectPerson"
  parameterType="int"
  parameterMap="deprecated"
  resultType="hashmap"
  resultMap="personResultMap"
  flushCache="false"
  useCache="true"
  timeout="10"
  fetchSize="256"
  statementType="PREPARED"
  resultSetType="FORWARD_ONLY">
</select>

官网地址：非常用参数介绍

mybatis – MyBatis 3 | XML 映射器

Mybatis获取参数的两种方式
- MyBatis获取参数值的两种方式：${}和#{}
  
  ${}的本质就是字符串拼接，#{}的本质就是占位符赋值
  
  ${}使用字符串拼接的方式拼接sql，若为字符串类型或日期类型的字段进行赋值时，需要手动加单引号；
  
  但是#{}使用占位符赋值的方式拼接sql，此时为字符串类型或日期类型的字段进行赋值时，可以自动添加单引号;
  
  #{} 方式近似的 JDBC 代码，
```
String selectPerson = "SELECT * FROM PERSON WHERE ID=?"; 
PreparedStatement ps = conn.prepareStatement(selectPerson); ps.setInt(1,id);
```
- 安全性方面：${}可能会引起sql注入 #{}方式不会；实际开发中建议使用#{}方式
单个字面量类型的参数
- 基本类型的parameterType可以简写例如 parameterType=“string”；parameterType=“int”

实体类类型的参数

#AreaMapper接口
Area selectByAreaParam(AreaParam areaParam);
#AreaMapper.xml
<select id="selectByAreaParam" parameterType="com.haierac.mybatis.example.param.AreaParam" resultMap="BaseResultMap">
    select * from vrv_area where area_name = #{areaName} and id = #{id}
  </select>

使用@Param标识参数

#AreaMapper接口
Area selectByAreaNameAndId(@Param(value = "areaName") String 
areaName,@Param(value = "id") Long id);
#AreaMapper.xml
<select id="selectByAreaNameAndId" resultMap="BaseResultMap">
    select * from vrv_area where area_name = #{areaName} and id = #{id}
  </select>

2、结果映射

返回实体类对象
- resultType=实体类名（若未开启别名配置则为全类名）
- 如果返回多条结果则报错
  
  org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 2
  
  #AreaMapper接口
  Area selectByAreaParam(AreaParam areaParam);
  
  #AreaMapper.xml <select id=“selectByAreaParam” parameterType=“AreaParam” resultType=“Area”>
  select * from vrv_area where area_name = #{areaName} and id = #{id} </select>
返回一个List<Area>结果同上

返回一个Map<String,Object>类型

结果为字段名+值{area_name=测试, update_time=2023-06-07 15:52:40.0, create_time=2023-06-07 15:52:40.0, project_id=1, level=1, parent_id=1, order_rule=1, machine_num=1, id=1, order_num=1}

#AreaMapper接口
Map<String,Object> getAreaMap(@Param(value = "areaName") String areaName,@Param(value = "id") Long id);
#AreaMapper.xml
<select id="getAreaMap" resultType="map">
    select * from vrv_area where area_name = #{areaName} and id = #{id}
  </select>

多条数据返回List<Map<String,Object>>类型
- 方式一
  
  结果：[{area_name=测试, update_time=2023-06-07 15:52:40.0, create_time=2023-06-07 15:52:40.0, project_id=1, level=1, parent_id=1, order_rule=1, machine_num=1, id=1, order_num=1}, {area_name=测试, update_time=2023-06-07 18:14:42.0, create_time=2023-06-07 18:14:42.0, project_id=2, level=1, parent_id=0, order_rule=1, machine_num=0, id=2, order_num=1}]
#AreaMapper接口
List<Map<String,Object>> getAreaListMap(@Param(value = “areaName”) String areaName);
#AreaMapper.xml <select id=“getAreaListMap” resultType=“java.util.Map”>
select * from vrv_area where area_name = #{areaName} </select>

方式二

结果：{1={area_name=测试, update_time=2023-06-07 15:52:40.0, create_time=2023-06-07 15:52:40.0, project_id=1, level=1, parent_id=1, order_rule=1, machine_num=1, id=1, order_num=1}, 2={area_name=测试, update_time=2023-06-07 18:14:42.0, create_time=2023-06-07 18:14:42.0, project_id=2, level=1, parent_id=0, order_rule=1, machine_num=0, id=2, order_num=1}}
```
#AreaMapper接口
@MapKey("id")
Map<String,Object> getAreaListMap2(@Param(value = "areaName") String areaName);
#AreaMapper.xml
<select id="getAreaListMap2" resultType="java.util.Map">
    select * from vrv_area where area_name = #{areaName}
  </select>
```

3、高级结果映射

一对一查询

imuSerialCode对应SystemDto 的属性imuSerialCode

javaType对应ImuSerialCode类型

#SystemDto实体类
@Data
@ToString
public class SystemDto extends System {

    private ImuSerialCode imuSerialCode;

}

#SystemMapper接口
SystemDto getSystemImu(Long id);

#SystemMapper.xml
<resultMap id="SystemImuResultMap" type="SystemDto">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
    <result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
    <result column="system_name" jdbcType="VARCHAR" property="systemName" />
    <result column="project_id" jdbcType="BIGINT" property="projectId" />
    <result column="external_machine_num" jdbcType="INTEGER" property="externalMachineNum" />
    <result column="inner_machine_num" jdbcType="INTEGER" property="innerMachineNum" />
    <result column="inductance_multiple" jdbcType="DOUBLE" property="inductanceMultiple" />
    <association property="imuSerialCode" javaType="ImuSerialCode">
      <id column="id" jdbcType="BIGINT" property="id" />
      <result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
      <result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
      <result column="create_account" jdbcType="VARCHAR" property="createAccount" />
      <result column="imu_serial_code" jdbcType="VARCHAR" property="imuSerialCode" />
      <result column="system_info_id" jdbcType="BIGINT" property="systemInfoId" />
      <result column="state" jdbcType="INTEGER" property="state" />
      <result column="imu_enable" jdbcType="VARCHAR" property="imuEnable" />
      <result column="timestamp" jdbcType="BIGINT" property="timestamp" />
      <result column="time_stamp" jdbcType="VARCHAR" property="timeStamp" />
      <result column="type" jdbcType="INTEGER" property="type" />
      <result column="is_charge" jdbcType="INTEGER" property="isCharge" />
      <result column="version" jdbcType="VARCHAR" property="version" />
      <result column="upgrade_time" jdbcType="TIMESTAMP" property="upgradeTime" />
      <result column="is_auto_acquire" jdbcType="CHAR" property="isAutoAcquire" />
      <result column="system_load" jdbcType="INTEGER" property="systemLoad" />
      <result column="low_standby" jdbcType="INTEGER" property="lowStandby" />
    </association>
  </resultMap>

  <select id="getSystemImu" resultMap="SystemImuResultMap" parameterType="long">
    select sys.*,imu.* from vrv_system sys left join vrv_imu_serial_code imu on sys.id = imu.system_info_id where sys.id = #{id}
  </select>

也可以定义一个SystemDto类，包含System类和ImuSerialCode类所需查询的属性，用resultType的形式接收（略）

<select id="getSystemImu" resultType="SystemDto" parameterType="long">
    select sys.*,imu.* from vrv_system sys left join vrv_imu_serial_code imu on sys.id = imu.system_info_id where sys.id = #{id}
  </select>

一对多查询

如果Project 和 System 的主键都为id 则System的id要起一个别名

sys.id as systemId

#ProjectMapper接口
ProjectDto getProjectDto(Long projectId);

#ProjectMapper.xml
<resultMap id="ProjectDtoBaseResultMap" type="ProjectDto">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
    <result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
    <result column="haier_contact" jdbcType="VARCHAR" property="haierContact" />
    <result column="haier_mobile" jdbcType="VARCHAR" property="haierMobile" />
    <result column="haier_position" jdbcType="VARCHAR" property="haierPosition" />
    <result column="is_default" jdbcType="INTEGER" property="isDefault" />
    <result column="join_time" jdbcType="TIMESTAMP" property="joinTime" />
    <result column="latitude" jdbcType="VARCHAR" property="latitude" />
    <result column="longitude" jdbcType="VARCHAR" property="longitude" />
    <result column="project_name" jdbcType="VARCHAR" property="projectName" />
    <result column="status" jdbcType="INTEGER" property="status" />
    <result column="user_company" jdbcType="VARCHAR" property="userCompany" />
    <result column="user_contact" jdbcType="VARCHAR" property="userContact" />
    <result column="user_mobile" jdbcType="VARCHAR" property="userMobile" />
    <result column="user_position" jdbcType="VARCHAR" property="userPosition" />
    <result column="city_code" jdbcType="BIGINT" property="cityCode" />
    <result column="country_code" jdbcType="BIGINT" property="countryCode" />
    <result column="industry_id" jdbcType="BIGINT" property="industryId" />
    <result column="province_code" jdbcType="BIGINT" property="provinceCode" />
    <result column="region_code" jdbcType="BIGINT" property="regionCode" />
    <result column="trade_id" jdbcType="BIGINT" property="tradeId" />
    <result column="device_type" jdbcType="INTEGER" property="deviceType" />
    <result column="address" jdbcType="VARCHAR" property="address" />
    <result column="corporate_name" jdbcType="VARCHAR" property="corporateName" />
    <result column="open_billing_service" jdbcType="INTEGER" property="openBillingService" />
    <result column="county_code" jdbcType="BIGINT" property="countyCode" />
    <result column="user_id" jdbcType="BIGINT" property="userId" />
    <result column="low_standby" jdbcType="INTEGER" property="lowStandby" />
    <result column="use_time" jdbcType="TIMESTAMP" property="useTime" />
    <collection property="systems" ofType="System">
      <id column="systemId" jdbcType="BIGINT" property="id" />
      <result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
      <result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
      <result column="system_name" jdbcType="VARCHAR" property="systemName" />
      <result column="project_id" jdbcType="BIGINT" property="projectId" />
      <result column="external_machine_num" jdbcType="INTEGER" property="externalMachineNum" />
      <result column="inner_machine_num" jdbcType="INTEGER" property="innerMachineNum" />
      <result column="inductance_multiple" jdbcType="DOUBLE" property="inductanceMultiple" />
    </collection>
  </resultMap>

<select id="getProjectDto" resultMap="ProjectDtoBaseResultMap" parameterType="long">
        select pro.*,sys.id  systemId,sys.create_time, sys.update_time, sys.system_name,
               sys.project_id, sys.external_machine_num, sys.inner_machine_num,
               sys.inductance_multiple from vrv_project pro left join vrv_system sys on pro.id = sys.project_id where pro.id = #{id}
    </select>

三、动态sql

if(where)

where 元素只会在子元素返回任何内容的情况下才插入 “WHERE” 子句。而且，若子句的开头为 “AND” 或 “OR”，where 元素也会将它们去除。
1. if一般搭配where标签同时使用如果不用where标签两个条件都不匹配则报错
2. 用where标签前面的AND 如果没用则会自动省略
  
  #AreaMapper接口
  List selectList(@Param(value = “areaName”) String areaName,@Param(value = “id”) Long id);
  
  #AreaMapper.xml <select id=“selectList” resultMap=“BaseResultMap”>
  select id, create_time, update_time, area_name, machine_num, parent_id, project_id,
  level, order_num, order_rule
  from vrv_area <where> <if test=“areaName != ‘’ and areaName!=null”>
  AND area_name = #{areaName} </if> <if test=“id != null”>
  AND id = #{id} </if> </where> </select>

choose (when, otherwise)

when匹配成功则不匹配otherwise，when都匹配不成功则匹配otherwise
#AreaMapper接口
List selectListChooese(AreaParam areaParam);

#AreaMapper.xml
<select id="selectListChooese" resultMap="BaseResultMap" parameterType="AreaParam">
    select id, create_time, update_time, area_name, machine_num, parent_id, project_id,
    level, order_num, order_rule
    from vrv_area
    where
        level = 1
      <choose>
        <when test="projectId !=null">
          AND project_id = #{projectId}
        </when>
        <when test="areaName !=null and areaName != ''">
          AND area_name= #{areaName}
        </when>
        <otherwise>
            AND id = #{id}
        </otherwise>
      </choose>
  </select>

trim (set)

下面的代码跟where标签功能类似
#AreaMapper接口
List selectListTrim(AreaParam areaParam);
```
#AreaMapper.xml
<select id="selectListTrim" resultMap="BaseResultMap" parameterType="AreaParam">
    select id, create_time, update_time, area_name, machine_num, parent_id, project_id,
    level, order_num, order_rule
    from vrv_area
    <trim prefix="where" prefixOverrides="and ">
      <if test="areaName != '' and areaName!=null">
        AND area_name = #{areaName}
      </if>
      <if test="id != null">
        AND id = #{id}
      </if>
    </trim>
  </select>
```
- prefix：
  - 表示在trim包裹的SQL语句前面添加的指定内容。
- suffix：
  - 表示在trim包裹的SQL末尾添加指定内容
- prefixOverrides：
  - 表示去掉（覆盖）trim包裹的SQL的指定首部内容
- suffixOverrides：
  - 表示去掉（覆盖）trim包裹的SQL的指定尾部内容
    set(<trim prefix=“set” suffixOverrides=“,”>与set功能类似)
#AreaMapper接口
int updateSet(@Param(value = “updateTime”)Date updateDate,@Param(value = “areaName”)String areaName,@Param(value = “id”)Long id);

#AreaMapper.xml <update id=“updateSet”>
update vrv_area <set> <if test=“updateTime!=null”>
update_time = #{updateTime,jdbcType=TIMESTAMP}, </if> <if test=“areaName!=null and areaName!=‘’”>
area_name = #{areaName,jdbcType=VARCHAR}, </if> </set>
foreach
foreach 元素的属性主要有 item，index，open，separator，close，collection。各属性含义如下所示。
- item 集合中元素迭代时的别名，该参数为必选。
  - index 在 list 和数组中，index 是元素的序号；在 map 中，index 是元素的 key。该参数可选。
  - open foreach 代码的开始符号，一般是 ”(“，和 close=“)” 合用。常用在 in()，values() 时。该参数可选。
  - separator 元素之间的分隔符，例如在 in() 的时候，separator=“,” 会自动在元素中间用 “,“ 隔开，避免手动输入逗号导致 SQL 错误，如 in(1, 2,) 这样。该参数可选。
  - close foreach 代码的关闭符号，一般是 ”)“，和 open=“(” 合用。常用在 in()，values()时。该参数可选。
  - collection 要被 foreach 标签循环解析的对象。
    具名参数 java 方法中使用了 @Param 注解指定了参数名称，则 foreach 中的 collection 属性必须为参数名
    匿名参数当在 java 方法中没有通过 @Param 注解指定参数名时，列表类型默认参数名为 ”list“，数组类型默认参数名为 ”array“，Map 对象没有默认值。
```
#AreaMapper接口
List<Area> getAreaIn(List<Long> ids);

#AreaMapper.xml
<select id="getAreaIn" resultMap="BaseResultMap">
    select <include refid="attr"></include>
    from vrv_area
    where id in
    <foreach item="item" collection="list" separator="," open="(" close=")" index="">
      #{item, jdbcType=NUMERIC}
    </foreach>
  </select>


#AreaMapper接口
 int batchInsert(@Param("areas") List<Area> areas);

#AreaMapper.xml
<insert id="batchInsert">
    insert into vrv_area (create_time, update_time, area_name, machine_num, parent_id, project_id,
    level, order_num, order_rule)
    values
    <foreach collection ="areas" item="entity" separator =",">
      (#{entity.createTime},#{entity.updateTime},#{entity.areaName},
       #{entity.machineNum},#{entity.parentId},#{entity.projectId},#{entity.level},#{entity.orderNum},#{entity.orderRule})
    </foreach>
  </insert>
```

四、mybatis的一级缓存和二级缓存

一级缓存时默认开启的

`flushCache`	如果将其设置为 true，将导致每当此语句出现时刷新本地和第二级缓存叫。默认值：对于选择语句。`false`
`useCache`	如果将其设置为 true，将导致此语句的结果缓存在二级缓存中。默认值：对于选择语句。`true`

#AreaTest
@Test
@Transactional(rollbackFor = Exception.class)
public void getAreaByNameAndIdCache(){
    Area area = areaService.getAreaByNameAndId("测试",1L);

    Area area1 = areaService.getAreaByNameAndId("测试",1L);

    Area area2 = areaService.getAreaByNameAndId("测试",1L);

    System.out.println(area);
}

#flushCache="true" 每次查询都刷新缓存
  <select id="selectByAreaNameAndId" resultMap="BaseResultMap" flushCache="true">
    select * from vrv_area where area_name = #{areaName} and id = #{id}
  </select>

二级缓存开启（非特殊情况不开启）

<cache
  eviction="FIFO"
  flushInterval="60000"
  size="512"
  readOnly="true"/>
这种配置创建了一个 FIFO 缓存，该缓存每 60 秒刷新一次，存储对结果对象或列表的 512 个引用，并且返回的对象被视为只读，因此 修改它们可能会导致不同线程中的调用方之间发生冲突。

可用的逐出策略包括：

*   `LRU`– 最近最少使用：删除在 时间。
*   `FIFO`– 先进先出：按对象进入缓存的顺序删除对象。
*   `SOFT`– 软引用：根据垃圾回收器状态和规则删除对象 软引用。
*   `WEAK`– 弱引用：根据垃圾回收器状态更积极地删除对象 和弱引用规则。

#缓存引用
<cache-ref namespace="com.someone.application.data.SomeMapper"/>

#AreaController
@GetMapping("/cache2")
    public void cache2(){
        AreaParam areaParam = new AreaParam();
        areaParam.setId(1L);
        areaParam.setAreaName("测试");
        Area area = areaMapper.selectByAreaParam(areaParam);
        System.out.println(area);
    }
#AreaMapper
Area selectByAreaParam(AreaParam areaParam);
#AreaMapper.xml

<cache
          eviction="FIFO"
          flushInterval="60000"
          size="512"
          readOnly="true"/>
<!-- useCache="true" 开启二级缓存 默认true  useCache="false" 关闭此查询的二级缓存 配置flushCache="true" 二级缓存也会失效-->
<select id="selectByAreaParam" parameterType="AreaParam" resultType="Area" useCache="true">
    select * from vrv_area where area_name = #{areaName} and id = #{id}
  </select>