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一、多表联合分页查询
多表联合查询结果集建议使用VO类，当然也可以使用resultMap
package com.cjhx.tzld.entity.vo;import com.baomidou.mybatisplus.annotation.IdType;import com.baomidou.mybatisplus.annotation.TableField;import com.baomidou.mybatisplus.annotation.TableId;import com.cjhx.tzld.entity.TContent;import com.fasterxml.jackson.annotation.JsonFormat;import io.swagger.annotations.ApiModel;import io.swagger.annotations.ApiModelProperty;import lombok.Data;import org.springframework.format.annotation.DateTimeFormat;import java.util.Date;@Data@ApiModel(value="TContentVo", description="内容池多表联合数据对象")public class TContentVo extends TContent { @ApiModelProperty(value = "编号") private Integer cid; @ApiModelProperty(value = "内容") private String title; @ApiModelProperty(value = "作者Id") @TableField("authorId") private Integer authorId; @ApiModelProperty(value = "时间") @JsonFormat(pattern="yyyy-MM-dd HH:mm:ss",timezone = "GMT+8") //返回时间类型 @DateTimeFormat(pattern="yyyy-MM-dd HH:mm:ss") //接收时间类型 private Date time; @ApiModelProperty(value = "内容") private String content; @ApiModelProperty(value = "作者姓名") private String author; @ApiModelProperty(value = "话题") private String topic; @ApiModelProperty(value = "模块编号") private int moduleNum; @ApiModelProperty(value = "模块") private String module; public TContentVo() { } public TContentVo(Integer cid, String title, Date time, String content, String author, String topic, int moduleNum) { this.cid = cid; this.title = title; this.time = time; this.content = content; this.author = author; this.topic = topic; this.moduleNum = moduleNum;}controller
package com.cjhx.tzld.controller;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;import com.baomidou.mybatisplus.core.metadata.IPage;import com.baomidou.mybatisplus.extension.plugins.pagination.Page;import com.cjhx.tzld.common.Result;import com.cjhx.tzld.entity.TContent;import com.cjhx.tzld.entity.TContentRelationFund;import com.cjhx.tzld.entity.TTopicPk;import com.cjhx.tzld.entity.vo.TContentVo;import com.cjhx.tzld.service.TContentService;import io.swagger.annotations.*;import org.springframework.transaction.annotation.Transactional;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;import java.util.Date;import java.util.List;@RestController@RequestMapping("/content")@Api("内容池模块")public class ContentController { @Resource private TContentService contentService; @ApiImplicitParams({ @ApiImplicitParam(name = "cid",value = "cid",dataType = "int",defaultValue = "0",required = false), @ApiImplicitParam(name = "title",value = "",dataType = "String",defaultValue = "",required = false), @ApiImplicitParam(name = "author",value = "作者姓名",dataType = "String",defaultValue = "",required = false), @ApiImplicitParam(name = "time",value = "发布时间",dataType = "Date",defaultValue = "",required = false), @ApiImplicitParam(name = "content",value = "内容",dataType = "String",defaultValue = "",required = false), @ApiImplicitParam(name = "topic",value = "话题",dataType = "String",defaultValue = "",required = false), @ApiImplicitParam(name = "moduleNum",value = "投放模块 1热点速递 2基会直达",dataType = "int",defaultValue = "",required = false), @ApiImplicitParam(name = "pageIndex",value = "页码",dataType = "int",defaultValue = "1",required = false), @ApiImplicitParam(name = "pageSize",value = "每页数量",dataType = "int",defaultValue = "10",required = false) }) @ApiResponses({ @ApiResponse(code = 200,message = "OK",response = TContent.class) @ApiOperation(value="分页获取内容接口(Web端)", notes="支持多条件查询",httpMethod = "GET") @RequestMapping(value = "/getContentPage",method = RequestMethod.GET) public Result getContentPage(@RequestParam(defaultValue = "0",required = false) int cid, @RequestParam(defaultValue = "",required = false) String title, @RequestParam(defaultValue = "",required = false) String author, @RequestParam(required = false) Date time, @RequestParam(defaultValue = "",required = false) String content, @RequestParam(defaultValue = "",required = false) String topic, @RequestParam(defaultValue = "0",required = false) int moduleNum, @RequestParam(defaultValue = "1",required = false) int pageIndex, @RequestParam(defaultValue = "10",required = false) int pageSize) throws Exception{ try { IPage<TContentVo> byPage = contentService.findByPage(new Page<TContentVo>(pageIndex, pageSize),new TContentVo(cid, title, time, content, author, topic, moduleNum)); return Result.success(byPage); }catch (Exception e){ return Result.serviceFail(e.getMessage()); } }}service
package com.cjhx.tzld.service.impl;import com.baomidou.mybatisplus.core.conditions.Wrapper;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;import com.baomidou.mybatisplus.core.metadata.IPage;import com.baomidou.mybatisplus.extension.plugins.pagination.Page;import com.cjhx.tzld.common.PageUtil;import com.cjhx.tzld.entity.TContent;import com.cjhx.tzld.entity.vo.TContentVo;import com.cjhx.tzld.mapper.TContentMapper;import com.cjhx.tzld.service.TContentService;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;import org.springframework.stereotype.Service;import javax.annotation.Resource;import java.util.Date;@Servicepublic class TContentServiceImpl extends ServiceImpl<TContentMapper, TContent> implements TContentService { @Resource private TContentMapper tContentMapper; @Override public IPage<TContentVo> findByPage(Page<TContentVo> page, TContentVo contentVo) { return tContentMapper.findByPage(page,contentVo); }}mapper
package com.cjhx.tzld.mapper;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;import com.baomidou.mybatisplus.core.metadata.IPage;import com.baomidou.mybatisplus.extension.plugins.pagination.Page;import com.cjhx.tzld.entity.TContent;import com.baomidou.mybatisplus.core.mapper.BaseMapper;import com.cjhx.tzld.entity.vo.TContentVo;import org.apache.ibatis.annotations.Param;public interface TContentMapper extends BaseMapper<TContent> { IPage<TContentVo> findByPage(Page<TContentVo> page, @Param("contentVo") TContentVo contentVo);}mapper.xml，注意入参contentVo
<?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.cjhx.tzld.mapper.TContentMapper"> <select id="findByPage" resultType="com.cjhx.tzld.entity.vo.TContentVo" parameterType="com.cjhx.tzld.entity.vo.TContentVo"> SELECT t.`cid`,t.`authorId`,a.`name`,t.`title`,t.`time`,t.`content`,p.`topic`,h.`title` AS `module` FROM `t_content` t LEFT JOIN `t_author` a ON a.`aid`=t.`authorId` LEFT JOIN `t_topic_pk` p ON p.`cid` = t.`cid` LEFT JOIN `t_hot_express` h ON h.`cid` = t.`cid` UNION ALL SELECT t.`cid`,t.`authorId`,a.`name`,t.`title`,t.`time`,t.`content`,p.`topic`,f.`title` AS `module` LEFT JOIN `t_fund_point` f ON f.`cid` = t.`cid` <where> 1=1 <if test="contentVo.cid > 0"> and cid = #{contentVo.cid}</if> <if test="contentVo.title != null and contentVo.title != ''"> and t.title like concat('%', #{contentVo.title}, '%')</if> <if test="contentVo.author != null and contentVo.author != ''"> and a.author like concat('%', #{contentVo.author}, '%')</if> <if test="contentVo.time != null"> and t.time =${contentVo.time}</if> <if test="contentVo.content != null and contentVo.content != ''"> and t.content like concat('%', #{contentVo.content}, '%')</if> <if test="contentVo.topic != null and contentVo.topic != ''"> and p.topic like concat('%', #{contentVo.topic}, '%')</if> <if test="contentVo.moduleNum == 1"> and f.currentState = -1</if> <if test="contentVo.moduleNum == 2"> and h.currentState = -1</if> </where> order by time desc </select></mapper>二、找不到mapper
首先排除@MapperScan("com.cjhx.tzld.mapper")已添加
首先配置文件扫描，mapper-locations:classpath:/com/cjhx/tzld/mapper/xml*.xml</include> </includes> </resource> </resources> </build>
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