Mybatis-Plus 多表查问分页

1. 在mapper外面定义方法

/* 第一种写法@Select("select c.* from tb_staff_customer_relation as scr left join tb_customer as c on scr.customer_id = c.id ${ew.customSqlSegment}")List<Customer> getListById(Page<Customer> page, @Param(Constants.WRAPPER) Wrapper wrapper);*//** * 第二种写法 */@Select("select c.* from tb_staff_customer_relation as scr left join tb_customer as c on scr.customer_id = c.id ${ew.customSqlSegment}")IPage<Customer> getListById(Page page, @Param(Constants.WRAPPER) Wrapper wrapper);

  • 解释:

    • page参数 com.baomidou.mybatisplus.extension.plugins.pagination.Page 须要导入此包
    • wrapper参数 com.baomidou.mybatisplus.core.conditions.Wrapper 须要导入此包
  • 固定写法,至于怎么失效的,我也不晓得呢

2. service调用mapper外面的办法

/** * 第二种写法,不应用page类  返回后果应用ipage */@Overridepublic List<CustomerResponseVo> getListByStaffId(int staff_id, int page, int limit) {    QueryWrapper<Customer> wrapper = new QueryWrapper<>();    // 查问条件    wrapper.eq("scr.staff_id", staff_id);    // 后果集排序    wrapper.orderByDesc("c.id");    IPage<Customer> customerIPage = staffCustomerRelationMapper.getListById(new Page(page, limit), wrapper);    ArrayList<CustomerResponseVo> arrayList = new ArrayList<>();    // 获取后果集    List<Customer> list = customerIPage.getRecords();    // 拼装返回数据    for (Customer customer : list) {        CustomerResponseVo responseVo = GemBeanUtils.copyProperties(customer, CustomerResponseVo.class);        arrayList.add(responseVo);    }    return arrayList;}

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