场景：数据库字段是下划线，程序中使用驼峰

目的：实现数据库下划线字段与实体中的驼峰属性映射

方式：设置map-underscore-to-camel-case属性为true来开启驼峰功能

1、application.yml配置

mybatis:
  mapperLocations: classpath:mapper/*.xml,classpath:mapper/base/*.xml
  configuration:
    map-underscore-to-camel-case: true

2、库表与实体

请注意库表中字段create_time对应实体中createTime

import com.picc.common.util.date.DateUtil;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;

import java.util.Date;

@Data
@ApiModel(description = "客户标签")
public class Lable{

    @ApiModelProperty("主键")
    private Long id;

    @ApiModelProperty("名称")
    private String name;

    @ApiModelProperty("机构")
    private String branch;

    @ApiModelProperty("类型1:公司,2:部门,3:个人")
    private String type;

    @ApiModelProperty("排序")
    private Integer sort;

    @ApiModelProperty("有无效标识1:有效,0:无效")
    private Integer valid;

    @ApiModelProperty("删除标识1:已删除,0:未删除")
    private Short deleted = 0;

    @ApiModelProperty(value="创建时间", example = "2021-02-01 00:00:00")
    private Date createTime = DateUtil.newDateTime();

3、SectionMapper.xml配置 

<?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.picc.vx.market.service.provider.dao.LableDao">

        <select id="count" resultType="java.lang.Long">
                select count(*) from m_lable
        </select>
      
</mapper>

4、查询结果

即实现下划线字段与驼峰式属性的完美映射！

[
    {
        "id":2,
        "name":"音响发烧友",
        "branch":"00000002",
        "type":"2",
        "sort":1,
        "valid":1,
        "deleted":0,
        "createTime":"2021-01-20 14:43:16"
    },
    {
        "id":3,
        "name":"影迷",
        "branch":"1",
        "type":"3",
        "sort":1,
        "valid":1,
        "deleted":0,
        "createTime":"2021-01-20 14:43:59"
    }
]