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Mybatis----传入参数parameterType类型详解

Mybatis----传入参数parameterType类型详解

前言

Mybatis的Mapper文件中的select、insert、update、delete元素中有一个parameterType属性,用于对应的mapper接口方法接受的参数类型。本文主要给大家介绍了关于MyBatis传入参数parameterType类型的相关内容,分享出来供大家参考学习,下面话不多说了,来一起看看详细的介绍吧。

1. MyBatis的传入参数parameterType类型分两种

1. 1. 基本数据类型:int,string,long,Date;

1. 2. 复杂数据类型:类和Map

2. 如何获取参数中的值:

2.1 基本数据类型:#{参数} 获取参数中的值

2.2 复杂数据类型:#{属性名} ,map中则是#{key}

3.案例:

3.1 基本数据类型案例

<sql id="Base_Column_List" > 
 id, car_dept_name, car_maker_name, icon,car_maker_py,hot_type 
 </sql> 
 <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Long" > 
 select 
 <include refid="Base_Column_List" /> 
 from common_car_make 
 where id = #{id,jdbcType=BIGINT} 
 </select>

3.2 复杂类型--map类型

<select id="queryCarMakerList" resultMap="BaseResultMap" parameterType="java.util.Map"> 
  select 
  <include refid="Base_Column_List" /> 
  from common_car_make cm 
  where 1=1 
  <if test="id != null"> 
   and cm.id = #{id,jdbcType=DECIMAL} 
  </if> 
  <if test="carDeptName != null"> 
   and cm.car_dept_name = #{carDeptName,jdbcType=VARCHAR} 
  </if> 
  <if test="carMakerName != null"> 
   and cm.car_maker_name = #{carMakerName,jdbcType=VARCHAR} 
  </if> 
  <if test="hotType != null" > 
   and cm.hot_type = #{hotType,jdbcType=BIGINT} 
  </if> 
  ORDER BY cm.id 
 </select>

3.3 复杂类型--类类型

<update id="updateByPrimaryKeySelective" parameterType="com.epeit.api.model.CommonCarMake" > 
 update common_car_make 
 <set > 
  <if test="carDeptName != null" > 
  car_dept_name = #{carDeptName,jdbcType=VARCHAR}, 
  </if> 
  <if test="carMakerName != null" > 
  car_maker_name = #{carMakerName,jdbcType=VARCHAR}, 
  </if> 
  <if test="icon != null" > 
  icon = #{icon,jdbcType=VARCHAR}, 
  </if> 
  <if test="carMakerPy != null" > 
   car_maker_py = #{carMakerPy,jdbcType=VARCHAR}, 
  </if> 
  <if test="hotType != null" > 
   hot_type = #{hotType,jdbcType=BIGINT}, 
  </if> 
 </set> 
 where id = #{id,jdbcType=BIGINT} 
 </update>

3.4 复杂类型--map中包含数组的情况

<select id="selectProOrderByOrderId" resultType="com.epeit.api.model.ProOrder" parameterType="java.util.HashMap" > 
  select sum(pro_order_num) proOrderNum,product_id productId,promotion_id promotionId 
  from pro_order 
  where 1=1 
  <if test="orderIds != null"> 
   and 
   <foreach collection="orderIds" item="item" open="order_id IN(" separator="," close=")"> 
    #{item,jdbcType=BIGINT} 
   </foreach> 
  </if> 
  GROUP BY product_id,promotion_id 
 </select>

4.注解@Param:这个比较特殊,但是很好理解

案例一:

@Param(value="startdate") String startDate :注解单一属性;这个类似于将参数重命名了一次

如调用mybatis的*mapper.xml中配置sql语句(DAO层)

List<String> selectIdBySortTime(@Param(value="startdate")String startDate);

则xml中的语句,需要配合@param括号中的内容:参数为startdate

<select id="selectIdBySortTime" resultType="java.lang.String" parameterType="java.lang.String"> 
 select distinct ajlcid from ebd_fh_ajlc where sorttime >= to_date(#{startdate,jdbcType=VARCHAR},'YYYY-MM-DD') and created_date=updated_date 
 and keyvalue in (select distinct companyname from ebd_fh_company_list where isupdate='0') 
 </select>

案例二:

注解javaBean,@Param(value="dateVo") DateVo dateVo;则需要注意编写的参数

List<String> selectIds(@Param(value="dateVo")DateVo dateVo);

对应的mapping文件

<select id="selectIds" resultType="java.lang.String" parameterType="com.api.entity.DateVo"> 
 select distinct ajlcid from ebd_fh_ajlc where sorttime >= to_date(#  {dateVo.startDate,jdbcType=VARCHAR},'YYYY-MM-DD') and created_date=updated_date 
 and keyvalue in (select distinct companyname from ebd_fh_company_list where isupdate='0') 
 </select>

至于要说优缺点的话,看个人喜好

总结

以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作具有一定的参考学习价值

原文  https://segmentfault.com/a/1190000021363738
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