mybatisPlus+多表联查+多条件分页查询（一对一，一对多分页）

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分页插件在分页时处理一对多的结构的情况时，总条数与实际条数不匹配。这时候需要自定义sql分页查询语句来实现一对多分页条件查询。希望能帮到你！

自定义mapper

package com.minglei.hotnews.mapper;


import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderDetailDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadParam;
import javafx.scene.control.Pagination;
import org.apache.ibatis.annotations.Param;

import java.util.List;

public interface ClientuserCustomMapper {
    /**
     * 根据工单ID获取详情
     * @param workOrderId
     * @return
     */
    WorkOrderDetailDto  loadWorkOrderDetailDto(Long workOrderId);
//    List loadWorkOrderDetails(WorkOrderLoadParam para);

    /**
     * 多条件分页显示工单
     * @param para
     * @return
     */
    List loadWorkOrderDetails(WorkOrderLoadParam para);

    /**
     * 多条件分页显示工单的工单数量
     * @param param
     * @return
     */
    Integer loadWorkOrderDetailsCount(WorkOrderLoadParam param);

    /**
     * 多条件分页显示工单
     *
     * @param page
     * @param param
     * @return
     */
    List loadWorkOrder(Page page, @Param("param") WorkOrderLoadParam param);
}

自定义mapper映射文件

    
        
        
        
        
        
            
            
            
        
        
            
            
            
        
    

    
        
        
        
        
        
            
            
            
        
        
            
            
            
        
    
    
        
        
        
        
        
            
            
            
        
    

    
        select
        w.id as id,
        w.addtime as addtime,
        w.ordernum as ordernum,
        w.shop_id as shop_Id,
        s.id as shopId,
        s.shopname as shopname,
        s.address as address,
        wlog.Id as logId,
        wlog.memo as memo,
        wlog.addtime as logaddtime from workorder as w
        left JOIN shop as s ON w.shop_id=s.id
        LEFT JOIN workoderlog as wlog ON w.id=wlog.workorder_id
        WHERE w.id=#{workOrderId,jdbcType=BIGINT}
    

    
        select
        w.id as id,
        w.addtime as addtime,
        w.ordernum as ordernum,
        w.shop_id as shop_Id,
        s.id as shopId,
        s.shopname as shopname,
        s.address as address,
        wlog.Id as logId,
        wlog.memo as memo,
        wlog.addtime as logaddtime from workorder as w
        left JOIN shop as s ON w.shop_id=s.id
        LEFT JOIN workoderlog as wlog ON w.id=wlog.workorder_id
        
            
            and w.ordernum like concat('%',#{OrderNum},'%')
            
            
            and s.shopname  like concat('%',#{ShopName},'%')
            
            
                and w.id in(select temp.id from( select distinct childw.id id from workorder childw LEFT JOIN shop childs ON childw.shop_id=childs.id   
                and childw.ordernum like concat('%',#{OrderNum},'%')
            
                
                    and childs.shopname  like concat('%',#{ShopName},'%')
                  limit #{PageNum},#{PageSize}) as temp)

            
        

    

    
        select count(temp.id) from( select distinct childw.id id from workorder childw LEFT JOIN shop childs ON childw.shop_id=childs.id   
        and childw.ordernum like concat('%',#{OrderNum},'%')
    
        
            and childs.shopname  like concat('%',#{ShopName},'%')
        ) as temp
    

    
        select
        w.id as id,
        w.addtime as addtime,
        w.ordernum as ordernum,
        w.shop_id as shop_Id,
        s.id as shopId,
        s.shopname as shopname,
        s.address as address
        from workorder as w
        left JOIN shop as s ON w.shop_id=s.id

        
        
            and w.ordernum like concat('%',#{param.OrderNum},'%')
        
        
            and s.shopname  like concat('%',#{param.ShopName},'%')
        
        
        ORDER BY w.id
    

定义接口service

package com.minglei.hotnews.service.WorkOrderService;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderDetailDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadParam;

import java.util.List;
import java.util.Map;

/**
 * 工单service
 */
public interface IWorkOrderLoadService {
    /**
     * 多条件分页显示工单
     * @param param
     * @return
     */
//    List loadWorkOrder(WorkOrderLoadParam param);
    Map loadWorkOrder(WorkOrderLoadParam param);

    /**
     * 使用mp自带分页查询工单
     * @param param
     * @return
     */
    Page  loadWorkOrderCustom(WorkOrderLoadParam param);
}

定义service接口实现类

package com.minglei.hotnews.service.WorkOrderService.Impl;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderDetailDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadDto;
import com.minglei.hotnews.mapper.ClientUserCustomDto.WorkOrderLoadParam;
import com.minglei.hotnews.mapper.ClientuserCustomMapper;
import com.minglei.hotnews.service.WorkOrderService.IWorkOrderLoadService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Component
public class WorkOrderLoadService implements IWorkOrderLoadService {
    @Autowired
    ClientuserCustomMapper clientuserCustomMapper;
    /**
     * 多条件分页显示工单
     *
     * @param param
     * @return
     */
    @Override
    public Map loadWorkOrder(WorkOrderLoadParam param) {
        Map workOrderRes=new HashMap<>();
        Integer aLong = clientuserCustomMapper.loadWorkOrderDetailsCount(param);
        workOrderRes.put("total",aLong);
        List workOrderDetailDtos = clientuserCustomMapper.loadWorkOrderDetails( param);
        workOrderRes.put("list",workOrderDetailDtos);
        return workOrderRes;
    }

    /**
     * 使用mp自带分页查询工单
     *
     * @param param
     * @return
     */
    @Override
    public Page loadWorkOrderCustom(WorkOrderLoadParam param) {
        Page page=new Page<>(param.PageNum,param.PageSize);
        List workOrderLoadDtos = clientuserCustomMapper.loadWorkOrder(page, param);
        return page.setRecords(workOrderLoadDtos);
    }
}