传递多个参数时示例

单表操作CRUD

插入

普通插入

• parameterType可选参数可不写，会自动匹配

• <insert id="insertOne" parameterType="com.mbyte.easy.admin.entity.Student">
      insert into student (name, img, sex, create_time)
      values (
          #{student.name,jdbcType=VARCHAR},
          #{student.img,jdbcType=VARCHAR},
          #{student.sex,jdbcType=INTEGER},
          #{student.createTime,jdbcType=TIMESTAMP}
          )
    </insert>

  回填主键

  
  useGeneratedKeys="true" keyProperty="id"

  <!--回填主键：useGeneratedKeys="true" keyProperty="id" -->
   <insert id="insertTwo" parameterType="com.mbyte.easy.admin.entity.Student" 
   useGeneratedKeys="true" keyProperty="id">
       insert into student (name, img, sex, create_time)
       values (
           #{student.name,jdbcType=VARCHAR},
           #{student.img,jdbcType=VARCHAR},
           #{student.sex,jdbcType=INTEGER},
           #{student.createTime,jdbcType=TIMESTAMP}
       )
  </insert>

  // 回填主键，执行完毕之后，student2中id自动赋值
  studentMapper.insertTwo(student2);
  // 直接可以获取到数据库生成的主键id
  student2.getId();
  System.out.println("student2:"+student2);

  批量插入

        

<insert id="insertBatch">
    insert into student (name, img, sex, create_time)
    values
    <foreach collection="studentList" item="student" separator=",">
        (
        #{student.name,jdbcType=VARCHAR},
        #{student.img,jdbcType=VARCHAR},
        #{student.sex,jdbcType=INTEGER},
        #{student.createTime,jdbcType=TIMESTAMP}
        )
    </foreach>
</insert>

删除

单个删除

<delete id="deleteSutdentById"  parameterType="java.lang.Long" >
    delete from student where id = #{id,jdbcType=BIGINT}
</delete>

<delete id="deleteByIds"  parameterType="java.lang.Long" >
    delete from student where id in
    <foreach collection="idList" index="index" item="item" 
    open="(" separator="," close=")">
        #{item}
    </foreach>
</delete>

更新

<!--注意字段判断-->
<update id="updateStuddent" >        
    update student
    <set>
        <if test="student.name != null">
            name = #{student.name,jdbcType=VARCHAR},
        </if>
        <if test="student.img != null">
            img = #{student.img,jdbcType=VARCHAR},
        </if>
        <if test="student.sex != null">
            sex = #{student.sex,jdbcType=INTEGER},
        </if>
        <if test="student.createTime != null">
            create_time = #{student.createTime,jdbcType=TIMESTAMP},
        </if>
    </set>
     where id = #{student.id,jdbcType=BIGINT}
</update>