mybatis-plus多表联合分页查询

1.entity层要写个Vo实体类

2.controller

@AutoLog(value = "员工CURD-分页列表查询")
@ApiOperation(value="员工CURD-分页列表查询", notes="员工CURD-分页列表查询")
@GetMapping(value = "/list")
public Result<?> queryPageList(EmployeeVo employee,
                        @RequestParam(name="pageNo", defaultValue="1") Integer pageNo,
                        @RequestParam(name="pageSize", defaultValue="10") Integer pageSize,
                        HttpServletRequest req) {
   //QueryGenerator.initQueryWrapper是jeecg-boot封装的查询,默认支持所有复杂的检索查询
   QueryWrapper<EmployeeVo> queryWrapper = QueryGenerator.initQueryWrapper(employee, req.getParameterMap());
   Page<EmployeeVo> page = new Page<EmployeeVo>(pageNo, pageSize);
   //自定义getAll接口
   IPage<EmployeeVo> pageList=employeeService.getAll1(page,queryWrapper);
   return Result.ok(pageList);
}

3.servlce

@Service
public class EmployeeServiceImpl extends ServiceImpl<EmployeeMapper, EmployeeVo> implements IEmployeeService {

  @Resource
  private EmployeeMapper employeeMapper;
    @Override
    public IPage<EmployeeVo> getAll1(Page<EmployeeVo> page, QueryWrapper<EmployeeVo> queryWrapper) {
        return employeeMapper.findByPage(page,queryWrapper);
    }
}

4.mapper.java

public interface EmployeeMapper extends BaseMapper<EmployeeVo> {
    /**
     * mybatis-plus多表查询
     * @param page
     * @param wrapper
     * @return
     */

    //参数加上@Param(Constants.WRAPPER),xml里加上${ew.customSqlSegment}可以实现复杂条件检索查询
    IPage<EmployeeVo> findByPage(IPage<EmployeeVo> page, @Param(Constants.WRAPPER) Wrapper<EmployeeVo> wrapper);
    
}

5.mapper.xml

<!--mybatis-plus多表联合查询,带上${ew.customSqlSegment就可以实现查询-->
    <select id="findByPage" resultType="org.jeecg.modules.demo.employeetest.entity.EmployeeVo">
        select employee.*,department.dep_name from employee left join department
        on employee.sys_org_code = department.id ${ew.customSqlSegment}
    </select>

6.查询出来的结果

{
  "success": true,
  "message": "操作成功！",
  "code": 200,
  "result": {
    "records": [
      {
        "createTime": "2020-10-14 16:35:36",
        "sex": "女",
        "name": "helloTest",
        "updateTime": "2020-10-14 16:41:41",
        "id": "1316296704307597313",
        "depName": "研发部",//这个是部门表中的字段,同过两表联查查询出来的
        "age": 23,
        "hobby": "打牌"
      },
      {
        "createTime": "2020-08-01 16:50:04",
        "sex": "男",
        "name": "萨芬",
        "updateTime": "2020-09-17 16:50:07",
        "id": "2",
        "depName": "人事部",
        "age": 12,
        "hobby": "阿斯顿"
      }
    ],
    "total": 2,
    "size": 10,
    "current": 1,
    "orders": [],
    "optimizeCountSql": true,
    "hitCount": false,
    "searchCount": true,
    "pages": 1
  },
  "timestamp": 1602729521729
}